HL Site is a Russian portal for some of Valve’s games.

HL Spain is a Spanish community for all Valve’s Half-Life games and mods, such as Counter-Strike, Day of Defeat or Team Fortress Classic. You can find previews, reviews, tutorials and news for everything related to HL and GoldSrc.

HL2 DM University’s mission statement is to promote and improve the online Half-Life 2 Deathmatch experience for all players by providing an extensive repository of useful and interesting information and files.

HL2Spain is a Spanish fan-site and gaming community covering everything about the Steam Platform, Valve Games, and Source Engine based Games & MODs. It includes news, reviews, previews, manuals and tutorials done by their team and the community itself.

HL2World.com is a news and forum based site that has been around for a long time. The forum is particularly active.

L4D.es is a website and Spanish Community dedicated to Left 4 Dead. Pagina web de Left 4 Dead en Español.

The L4D Map Database is a library of all Left 4 Dead maps (official and custom) in the form of a wiki that anyone can contribute to. Includes downloads, screenshots, videos, information, and more for each map.

L4D Maps is a website completely dedicated to Left 4 Dead and everything about it.

L4DMods.com covers everything, and I mean everything, related to the L4D community.

Leak Free is a Source engine development community started in 2004, which consists of useful tutorials and a helpful community to answer all of your level design, modeling, and programming questions. One of the most noted features is the Valve Hammer Editor Error Listing, which describes all the errors in the software and how you [...]

Left 4 Dead 411 looks like the perfect place to start if you are new to the game. It contains plenty of help for new players.