| Name | Service | |
|---|---|---|
| Arbitrary Imposition | Site dedicated to the Gman and his sightings | |
| Weapons of Day of Defeat | Weapons of Day of Defeat | |
| Sven Co-op | Great website with a very active community for the Sven Coop Mod | |
| Weapons of Team Fortress 2 | Weapons of Team Fortress 2 | |
| Weapons of Insurgency 2 | Weapons of Insurgency 2 | |
| headcrab.pl | Polish community dedicated to Half-Life | |
| The Wall | German Mapping community with a wealth of Tutorials | |
| No Draw | Great Blog detailing concepts when it comes to TF2 map creation | |
| hl2modcentral | A site that had a wealth of useful tutorials but unfortunately lost. | |
| EditLife | One of the older sites dedicated to mapping and resources. No longer live  | |
| /r/steam | /r/steam | |
| /r/TF2 | /r/TF2 | |
| EGIR.DK | Provided a vibrant forum and tutorial collection back in the day | |
| Half-Life Museum | A good break down of Half-Life and Half-Life 2, unfortunately it is no longer live. | |
| Steamcast | Great collection of Podcasts on everything VALVe | |
| Valve Developer Union | the Valve Developer Union’s goal is to preserve the toolset and knowledge for modding Quake-based games, including games built off Valve Corporation’s GoldSrc and Source engines. | |
| Official twitter for Valve Software | Official twitter for Valve Software | |
| Official twitter for TF2 | Official twitter for TF2 | |
| Counter-Script | The #1 Counter-Strike Scripting Site... now gone :/ | |
| Texture Studio | Old texture resource for Half-Life, contains some tutorials | |
| Dota Wiki | Encyclopedia of Dota | |
| Half-Life: Alyx | The Official Half-Life: Alyx Website | |
| SteamDB | Records all changes to steams games and products | |
| The Wadfather | Contains some useful links to tutorials | |
| HL Improvement | Thriving Modding Community | |
| Background Radiation | Unfortunately dead, this site provided prefabs back in the day | |
| Amphibian Mods | Another great resource for modding, unfortunately lost in Valvetime | |
| Half-Life Arrangement | Few small tutorials for Source | |
| csgo_servers | Official mailing for CS:GO Servers | |
| Rvanhoorn | Half-Life 2 Map Editing Optimization Guide | |
| 3rdLife | very hard to crawl but was once a great tutorial resource | |
| HL Collection | Russian Mod hosting site dedicated to Half-Life | |
| scmapdb | Tutorials for Sven Co-op | |
| Petes Place | Old coding tutorials | |
| Map Core | Legendary Half-life Based Mapping Resource with a Vibrant community | |
| Facepunch | Great website with plenty of tutorials many of which focus on Garrys mod but none the less a very useful website | |
| /r/csworkshop | /r/csworkshop | |
| Podcast 17 | Another great collection of podcasts on anything steam, valve or source related | |
| Half-Life 2 Mods | A collection of all known mods for HL2 | |
| Weapons of Counter-Strike: Condition Zero | Weapons of Counter-Strike: Condition Zero | |
| modsentry | Great resource covering popular game mods | |
| hlds_announce | Official mailing for Half-Life Dedicated Server Announce | |
| Half-Life Beginners guide | Decent attempt to make it easier for newbs to come to grips with the SDK | |
| Planet Fortress | Team Fortress Based fan site | |
| Weapons of Day of Defeat: Source | Weapons of Day of Defeat: Source | |
| Thinking with Portals | The Official Portal Website | |
| /r/Halflife | /r/Halflife | |
| Half-Life SDK2 Resources | Good site for getting up and running with the old SDK | |
| HalfLife.net | Another Half-Life website from back in the day | |
| half-life.ru | Active Russian Modding Community | |
| Weapons of Half-Life 2 | Weapons of Half-Life 2 | |
| ModMatic | Mod review site from the developer of Minerva | |
| Resource Code | Old site with large collection of coding tutorials written in German | |
| Level Design Theory | Blog documenting single player map creation for Half-Life 2 and other Source Games | |
| HL2DM University | Half-Life 2 Deathmatch based community resource. | |
| Weapons of Left 4 Dead | Weapons of Left 4 Dead | |
| metrocop | Comics from Source engines games, specifically Garrys Mod. | |
| Sourcedc | Had some decent Mapping tutorials, Worth a look. | |
| Half Life Saga | not useful for modders but a must read for those interested in the half-life Universe | |
| Half-life Coding Index | Old site indexing the coding tutorials available for half-life | |
| hl.loess | Very useful list of mods for Half Life | |
| A Working Pig | Half-Life 2 Deathmatch maps and utilities | |
| dying2kill | Australian & NewZealand based Gaming Community | |
| Phineas Bot | Bots for Half-Life and tutorials | |
| VDC | The Valve Developer Community is the official Source SDK Documentation | |
| gamewag | Links to plenty of mapping and modding tutorials based on Source | |
| Wallworm | Modeling tools for Max | |
| KV File Generator | Online tool that automatically generates a formatted .kv file based on your selection for CS:GO | |
| Run Think Shoot Live | A great community website for all things valve related. Focused on mods, tutorials and the expression of the community. Previously known as Planet Phillip. | |
| Weapons of Counter-Strike Online | Weapons of Counter-Strike Online | |
| Wavelength | Source, GoldSrc tutorials, inactive forums, mostly defunct, use the wayback machine to get some missing pages | |
| Botmans Bots | Decent starting point for modding the SDK | |
| Half-Life | The Official Half-Life Website | |
| Half-Life Programming | Great resource for Half-Life coding | |
| Official twitter for DOTA2 | Official twitter for DOTA2 | |
| Counter Strike Wiki | Encyclopedia of Counter Strike | |
| Weapons of Vampire the Masquerade: Bloodlines | Weapons of Vampire the Masquerade: Bloodlines | |
| Contaminated | Defacto place for everything half-life around its release. Closed only to re-open as Planet Half-life. | |
| Day of Defeat Wiki | Encyclopedia of Day of Defeat | |
| Half Life Express | Old site for news on Half-Life | |
| Half-Life 2: Episode 1 | The Official Half-Life 2: Episode 1 Website | |
| Chaincraft | Olden goldie here with some very useful modding tips on goldsrc | |
| Half-Life Fallout | One of the better communities for Half-life content | |
| The 303 | Tutorials for Source | |
| Weapons of Black Mesa | Weapons of Black Mesa | |
| MaxofS2D | Gifted movie maker and modeler who worked extensively with Source... | |
| NerdChow | Coding tutorial for Half-Life | |
| Game Banana | One of the original game modding websites (previously known as FPS Banana) | |
| /r/sourceengine | /r/sourceengine | |
| Moddb | Huge Database of Mods, tools and tutorials, thriving community and useful rating system | |
| Jinx's Maps | Great little site with some good tutorials and resources on Half-life | |
| hlds_linux | Official mailing for Half-Life Dedicated Servers on Linux | |
| Half-Life Mods Wiki | Encyclopedia of Half-Life Mods | |
| Halflife2.filefront | Huge collection of downloads for Half Life and Source | |
| Chaosincarnate | Tools and Tutorials for Source Modding | |
| SRCDS | Source Dedicated server resource | |
| World of Level Design | Tutorials on Mapping for many platforms | |
| Counter Strike: Global Offensive, Counter Strike: Source | The Official Counter-Strike Website | |
| Half-Life 2: Episode 2 | The Official Half-Life 2: Episode 2 Website | |
| Slackiller | Tutorials, textures and maps for Source | |
| Ubermicro | Community of tutorials on mapping and modding | |
| HL2 Coding | Programming Tutorials for HL2 | |
| Persistence of Vision | Tutorials on creating movies in half-life | |
| Plague Fest | Great mapping and modding community | |
| /r/Portal2 | /r/Portal2 | |
| hl2world | No longer exists but was once the defacto source of tutorials for HL2 Modding | |
| hlcoders | Official mailing for Half-Life Coders | |
| /r/DotA2 | /r/DotA2 | |
| Netday | Map hosting site including but not limited to Valve Games | |
| /r/L4D2 | /r/L4D2 | |
| Left 4 Dead 2 | The Official Left 4 Dead 2 Website | |
| Half-Life HQ | Once a very busy site for Half-Life | |
| isolated-design.de | A good resource for GoldSrc modding tutorials | |
| The Orange Box | The Official Orange Box Website | |
| Garrys Blog | From the creator of Garrys mod comes Garrys Blog... | |
| VERC | VERC Collective (Valve Editing Resource Center) website no longer exists but can be traversed on the wayback machine, Predecessor to VDC | |
| Half-Life Library | This site focuses more on user generated content like custom maps, modifications, videos, models, clans and more for all of Valve's games. | |
| The Snarkpit | Host for maps, tools and tutorials, active community | |
| Half Life Machinima Wiki | Encyclopedia of Half Life Machinima | |
| Design 3 (Noesis) | Big collection of high quality Source engine tutorials (paid) | |
| Planet Half-Life | Once one of the greatest sources for everything HL2, is now shutdown with Gamespys closure | |
| Ceskemody | Czech Modding site with both GoldSrc and Source Content | |
| Half-Life Physics Reference | The Half-Life Physics Reference is a wonderful site with un-official documentation on the GoldSrc Engine. | |
| Official mailing lists | Ask questions related to mapping, coding and steam services through each mailing list, view the archives as well! | |
| WorldCraft Online | Tool for creating Hammer maps from a 2D perspective | |
| Garry's Mod Wiki | Wiki with useful information for developers and gamers playing with Garry's Mod | |
| Type 3 studios | Source Engine mapping and tutorials | |
| Steam Review | Site covering interesting facts about Steam | |
| Half-Life Programming Planet | plenty of good old tutorials here for Half-Life | |
| pcosmos.ca | Collection of Half-Life and Opposing Force Mods | |
| Black Mesa | Black Mesa is a re-envisioning of Valve Software's classic science fiction first person shooter, Half-Life. Powered by Source Engine, You will re-visit the inaugural role of Gordon Freeman and his memorable journey through the Black Mesa Research Facility. | |
| /r/valve | /r/valve | |
| Half-Life Editing Resource | Similar to VERC, decent collection of tutorials here as well as downloads | |
| SFMLab | Download free models for use in your Source Filmmaker shorts | |
| 100 Half-Life 1 Mods | 100 of Half-Life 1's best Mods hand picked by Andrej Mernik | |
| Valvetime | Great source of news on everything Valve related. | |
| HL2Spain | Spanish site covering everything Source | |
| TWHL | Source, GoldSrc tutorials, active forums, friendly community | |
| Counter Server Maps | Another unfortunately dead resource that supplied plenty of downloads and tutorials | |
| ModDota | Great resource for modding Dota II | |
| Game Edit | Few small tutorials on HL1 mapping | |
| HL2DB | Another lost site that had some promise back in the day. | |
| The Razzer Tutorials | Tutorials for Source mapping (Deutsch) | |
| Left 4 Dead Wiki | Encyclopedia of Left 4 Dead | |
| Weapons of Half-Life | Weapons of Half-Life | |
| nashalife | Russian Modding site for Half-Life | |
| hlds | Official mailing for Half-Life Dedicated Servers | |
| Weapons of Source Film Maker | Weapons of Source Film Maker | |
| /r/Hammer | /r/Hammer | |
| Steampowered Forums | The Original Official Steam Forums | |
| HLDS 101 | Cool resource explaining how to use the Half-Life Dedicated Server | |
| nextwish | Old site with useful info on modding for GoldSrc | |
| Mods Inside | Russian Mod community providing forums, files and reviews. | |
| Half-Life 2 | The Official Half-Life 2 Website | |
| Grinder74 | Another Polish community dedicated to Half-Life | |
| Team Fortress Wiki | Encyclopedia of Team Fortress | |
| Weapons of Firearms: Source | Weapons of Firearms: Source | |
| Handy Vandal | Decent oldschool resource for half-life modding | |
| SourceWiki | Once had some good coding tutorials and offered help, unfortunately lost. | |
| Alien Swarm:Single Player Blog | Great Blog based on the Single player conversion mod for Alien Swarm | |
| Halfwit 2 | HL2 mapping and tutorials, general information | |
| taz00 | Some useful source modding tips can be crawled here | |
| When its done | Some tutorials on HL1 development | |
| CITY17.RU | Another unfortunate victim of disregard, CITY17.ru was a great site dedicated to everything Half-life. | |
| Mapping Base | Great German community for Mapping resources. | |
| HL2 Mods.ru | A Russian Mod Review site for Source Games | |
| Weapons of Counter-Strike | Weapons of Counter-Strike | |
| /r/SourceMods | /r/SourceMods | |
| The Fixxxer | Good collection of coding tutorials here | |
| Gamedesign.net Prefabs | hosted multitudes of prefabs for half-life | |
| /r/CounterStrike | /r/CounterStrike | |
| Radium | Old Map rating and review site | |
| Nems Tools | Extremely useful tools for Source modding | |
| Vanilla Capsule | decent pipe tutorial for Hammer | |
| HL Spain | Spanish blog covering Half-Life 1 Mods | |
| Half-Life Fusion | French site dedicated to Half-Life | |
| valvenews | Old site for news on Half-Life | |
| Weapons of Insurgency | Weapons of Insurgency | |
| Mr Funeral Mods | Talented Source Modder with good quality Tutorials | |
| Mapeadores | Spanish modding Tutorials | |
| Half-Life Wiki | Encyclopedia of Half-Life | |
| Half-Life DeathMatch Guide | Guides for succeeding in HL1DM | |
| Action Half-Life | Useful maps and Tutorials (use the wayback machine to navigate) | |
| 3kliksphilip | Talented CSS and CS:GO Mapper with a wealth of Tutorials | |
| Modding Area | Great French community for Modding resources. | |
| Source Runs | Source runs is a great site documenting and supporting community members who attempt record breaking speed runs through GoldSrc and Source Engine games. | |
| Alien Swarm Wiki | Encyclopedia of Alien Swarm | |
| /r/AskMappers | /r/AskMappers | |
| Half-Life Portal | German site covering Valves games | |
| /r/csmapmakers | /r/csmapmakers | |
| Dota II | The Official Dota 2 Website | |
| The Mighty Atom | Great little selection of some of the harder to find resources on Half-life | |
| Leakfree | Some useful tutorials on mapping with Source | |
| SDK Nuts | One of the older HL2 modding websites | |
| Vossey | Active French Modding Community | |
| Interlopers | HL2 News, Tutorials and forum with a thriving community | |
| Half-Life Coding | one of the best original resources for Half-Life Coding | |
| TenFour | Once a great review site. | |
| Half-Life Nostalgia Project | Collection of screens and info prior to the release of Half-Life. another victim to gamespys untimely demise. | |
| HLFX | Active Russian Modding Community | |
| Half-Life Beta Project | Nice little russian site covering Half-Life designed around the old steam colors. | |
| Weapons of Counter-Strike: Global Offensive | Weapons of Counter-Strike: Global Offensive | |
| Official twitter for L4D | Official twitter for L4D | |
| /r/SourceEngineTest/ | /r/SourceEngineTest | |
| Half Life Zone | Small site for Half life related content | |
| Half-Life Comic | Comical take on the Half-Life Universe | |
| Combine OverWiki | Comprehensive information on Half-life and Portal | |
| /r/Portalmaps | /r/Portalmaps | |
| Mortal Dev | Great website with links to useful resources | |
| Wunderboy | Very useful Tools and Tutorials for Source Modding | |
| GoldSrc Gold | Exhibiting and preserving the great look and feel of Goldsource engine games & mods from days gone bye. | |
| Weapons of Left 4 Dead 2 | Weapons of Left 4 Dead 2 | |
| Where is Gordon Freeman | This website is a timeline documenting the range of fascinating events that have happened between Gordon Freeman’s most recent appearance in 2007 and his yet-to-be-announced next appearance in the franchise. | |
| Counter-Strike Planet | Great old mapping resource for Counter strike. | |
| HalfLife Control Unit | Great web resource for Half-Life | |
| Appalachian Killing Grounds | Old site with large collection of tutorials | |
| Half-Life [GameHut] | Old site with walkthroughs on half-life | |
| The Weapons Workshop | provided downloads to Hl Models. | |
| /r/Sourceengine2 | /r/Sourceengine2 | |
| Team Fortress 2 | The Official Team Fortress Website | |
| Counter Map | Useful maps and Tutorials for CS 1.6 and CS:S | |
| Editing Archive | The Archive serves as a gathering point for people interested in games and game development. The Archive has various features to help unite the community, and bring them together. | |
| Left 4 Dead | The Official Left 4 Dead Website | |
| Official twitter for CS:GO | Official twitter for CS:GO | |
| Gaming-Models.de | Download free models for use in your mods | |
| Mach III | Decent site from the old days covering Half-Life | |
| Half-Life.org | Some interesting articles to read here | |
| Weapons of Counter-Strike: Source | Weapons of Counter-Strike: Source | |
| tophattwaffle | Excellent tutorials on Source mapping | |
| Half-Life Wiki | Another great wiki covering Half-Life | |
| /r/Portal | /r/Portal | |
| ammahls | Tutorials for Sven Co-op | |
| /r/SFM | /r/SFM | |
| CS:Velocity | Once another vibrant community from the Counter Strike golden days | |
| Ask Yahn | Questions put to Valve Employee Yahn Bernier | |
| Half-Life Creations | Useful Community for modding tutorials | |
| 69th Vlatitude | Good oldschool tuts and resources can be found here | |
| LambdaGeneration | A great community fan website for all things Valve related with a primary focus on that which is Half life. Gives great exposure for new mods. |