Valve Community

Obsidian Conflict is a co-operative modification created for Half-Life 2. It is a community based mod with focus on fun, co-operative and physics-related puzzles. The mod has an open story, but is still set in the Half-Life 2 universe.

Steam Friends covers all the news related to Steam and Valve.

Zombie Panic: Source is a survival horror MP HL2 modification. Play as either the survivors or the undead, trying to wipe each other out or completing objectives to escape the horror.

HL Improvement is dedicated to the creation of custom content for all things Valve related. With tons of custom content, and a friendly community. What could go wrong?

Half-Life Creations provides a professional atmosphere for third party developers. Forums, downloads and even hosting for modifications are availble on this friendly site.

Half-Wit 2 is packed with tutorials, guides and other useful bits of information to help anyone creating custom content for the Source Engine. There is plenty of good stuff here and well worth checking out.

Mod DB is the largest website dedicated to supporting independent development of games, including mods, indie games, and user generated game content.

The Whole Half-Life AKA TWHL is first and foremost a community of mappers and modders. It has very active forums and plenty of tutorials. There are also a lot of tutorials for various aspects of modding. In addition to regular mapping competitions there is also a Map Vault, which contains both finished maps and a lot of WIP as well.

The Snarkpit has been online since 2001, making it one of the longest running websites that covers Valve’s games. It has had a number of redesigns over the years and always adds new features. It’s focus is maps and mods for a wide variety of games and mods. The site has an active forum and plenty of downloads. Many of the articles are quite short but they are still a good read.

Interlopers has been online since 2004. It posts selected Steam game news but its focus is on content creation. The main part of the site is its forum, where visitors discuss a wide range of gaming topics. A recent new feature is Portfolios that has been a great success. In addition to this there are also tutorials, articles and downloads.