If your using a MAC I would suggest Mini-Cad, it's easy to learn the
basics, many architect's that use Mac's also use Mini-Cad. It has good 3-D
capabilities, but the rendering has to be done with another program.  It's
easy to plug in Pict and EPS images and type. I've used it for about ten
years now and its following is growing which is a positive indication that
the program has strength.  It is also ported to the, dare I say it? Bill
Gates type machines, so it will probably be seen more in that field.  Stay
away from blueprint it's a waste of money.
PS: The company gives good tech support also.