Tweakfactor
- Performance optimaisation site. Includes breakdown of the performance hit of each in-game graphics option.
- http://www.tweakfactor.com/articles/tweaks/codtweak/

GameFAQs
- Links to user-submitted walkthroughs. Includes weapon and level guides, as well as a cheat section.
- http://www.gamefaqs.com/computer/doswin/game/914586.html

Cod Utility
- With gallery, server admin tutorial and forums. Registration required for downloads area with maps and mods.
- http://www.codutility.com

Call of Duty nation
- Offers forums, maps, mods and skins for Call of Duty and United Offensive. Also with a movie of Call of Duty 2.
- http://www.codnation.com/

IGN
- Collection of cheat codes, FAQs, walkthroughs, reviews, features, movies, screenshots, news and boards.
- http://pc.ign.com/objects/550/550042.html

Infinity Ward Nation
- News, image gallery, downloads, FAQ, developer information, and discussion forums.
- http://www.iwnation.com/

After-Hourz
- Offers server rentals for WW2-based shooters. Includes discussion forums, rules, downloads, and photo gallery.
- http://www.after-hourz.com/cod/