Bryce 5.0 is being offered free on their
website until September 6, 2006. I'd never used it before, but since its a $100 or so program, I couldn't resist. Its fun! I wish I could afford the time and money to take a class on it, but for right now I'll settle for fiddling. Examples of what I've managed so far, proof that an amateur has a chance at making something halfway decent...
and
http://img183.imageshack.us/img183/4787/roseorbsie8.jpg (opens huge, desktop wallpaper size)