There are at least a few free video tutorials that show you the basics of using the 3D camera in After Effects. Here's a couple:
The Fox Classics Promo tutorial by John Dickinson.
Be A Good Parent To A Camera by Alan Shisko.
Working with Null Objects in AE by Aharon Rabinowitz.
Andrew Kramer has one too, somewhere...maybe iTunes.
Articles by Trish & Chris Meyer -- Camera Control, Part 1: Auto-Orient & Orbit and Camera Control, Part 2: Graph Editor & Dolly Rigs; plus a video, After Effects Apprentice Video Tutorial #7: Manipulating 3D cameras as well as views.