http://www.microsoft.com/com/news/drgui.asp
Description: It is a seven part guide to basic COM. It also has information on more advanced COM.

http://www.develop.com/tutorials/com/logon.asp
Description: A tutorial on COM complete with practive labs and exercises

http://www.telefragged.com/Q2BotCore/
Description: The client-side BOT for Quake 2

http://www.microsoft.com/xml/
Description: Microsoft XML Parser

http://www.techvanguards.com
Description: Tutorials and Help with COM technology.