Brothercake put it best, Photoshop 6 is great. It took me a little bit to get used to--my sister got it free from college and I just started messing with it one day--but after the learning curve was over, my is it a wonderful program!
I have never messed with a 3D program mainly because of the cost vs. need. Most people I know with a good 3D program have it through illegal means, and that just isn't my way. I will second brothercake again and say that terragen is quite fun to mess around with, and it's free!!