This piece of software is free and fairly intuitive. I got it two days ago and have been pretty happy with the themes I could create. It has a setting to create 240x240 and 480x480 themes. I just posted some under the NFL thread if you want to see what it can do in the hands of an idiot.
Check it out-
http://www.freewarepocketpc.net/ppc-...ence-v1-6.html