I've got a couple of Auto Desk programs that I use.
Auto Sketch Release 9 and Auto Cad 2006.
If you've never used a drawing program, you need to start with something that's fairly easy to learn, and then move up as you get the hang of it.
I attended a technical college (at night) to learn Auto Cad .
It's definitely not a good program for a beginner (unless you have a teacher)...plus, it's expensive.
The Auto Sketch program is a lot less "involved" (i.e. complicated), plus you can get a copy for around $50.
It has a good symbol library, and works well when creating floor plans and electrical drawings....or any drawing in general.
The Auto Cad program has all of the "bells and whistles", hundreds of commands, and is difficult to learn....but...you can create any type of drawing that you choose, and is really a great tool once you get the hang of it.
steve