[rikkersc]

I use the Wacom Intuos 3. The actual usable tablet area is 4.5" x 5.5". I love it and it works for all the photo editing I do.

If you aren't sure about which size or kind you like, you could try them out at the store first. THat wasy you can see how they fit and work with what you want to do.
I was "positive" I wanted a LARGE tablet, the bigger the better, I thought. Then I saw the prices and realized that may never happen. So, I tried them out and found out that the smaller size actually worked better for what I want to do and fit my hand motions much, much better. It was also a little more affordable, even though I didn't go with the cheapest. I wanted what would work for me, and if that was a huge one, then that is what I would have aimed for, but it turns out a smaller one was better.