Help with AutoCAD 3D

As you know, I'm an interior designer...the largest part of my job is creating construction documents. In an effort to broaden my skills and grow, I am trying to learn how to use 3D in AutoCAD Architecture 2008. If you know of a good web site where I can find tutorials or you know of an inexpensive class going on here in the south, would please leave a comment? Your help is greatly appreciated!