• http://www.avault.com/pcrl/
• http://www.gamerankings.com
• http://www.pcgameworld.com/
• http://www.worthplaying.com 
• http://gamespot.com/
• http://www.pcgamer.com
• http://www.happypuppy.com
• http://www.fileplanet.com/
• http://download.cnet.com/
• http://www.zdnet.com/downloads/

• A Modification :

One of the better places to get new coop map packs or levels is: http://www.levels4you.com 

SOFTWARE - Misc.links

• More necessities 
•  
• Alcohol 120%
• Virtual CD

More awesome sites you need to bookmark.

• http://www.savegames.net/ 
• http://www.makeabackup.com 

 I was able to get most games up and running with NO CD in minutes with the help from this great site: 

http://www.gamecopyworld.com

See a list of cooperative PC games