Mental Ray Demonstration of use in film:
http://www.mentalimages.com/gallery/motion-pictures.html
Source Demonstration of use in trailers:
http://store.steampowered.com/search/?advanced=0&term=valve&category1=999
Source Developers wiki for their SDK:
http://developer.valvesoftware.com/wiki/SDK_Docs
Machinima.com, online source for videos made using existing game tools:
http://www.machinima.com/
Free web resource for making graphs. This was used to make the flowcharts that I used to organize my process
http::/www.gliffy.com
VTFLib- a program to view assets in the source engine
http://nemesis.thewavelength.net/index.php?p=40
Steam Forums: Art and Video discussions
http://forums.steampowered.com/forums/forumdisplay.php?f=819
Tutorial on adding assets to the steam engine
http://forums.tf2maps.net/showthread.php?t=838