If you're investigating CAD platforms, you might find it helpful to take a look at the Using IntelliCAD guide which is available at lulu.com in ebook and printed formats.
Using IntelliCAD describes how to use IntelliCAD to draw in 2D and 3D, view drawings, dimension entities, work with layers, insert blocks and external references, add custom programs, and everything else you expect from a CAD program.