I've never used a CAD program before but have recently come across the notion that I could design an iPhone case to be sold on Shapeways (or a similar site - haven't done the research yet. I need to do some experimenting, but am an artist and have sold work on sites like Zazzle and CafePress. I'm looking to take my artwork to another level. Who can get me started?
I would first start by doing some simple tutorials for you particular CAD software before you can start making your artistic creations. You need to learn how to use the basic tools first.