Here are some articles from Digital Producer Magazine that I found worthy...
A 3 part series entitled "Combustion 2 for After Effects Users" designed to help explain things....Nicely written by Kevin Schmitt.....
Part 1: Working with Illustrator files
Part 2: Working with Photoshop files
Part 3: A birds-eye view of the C2 interface
And NEXT, Just for MAC Combustion Users... "How to Speed Up Your Combustion MAC performance!"