I would definitely go with a Wacom. I believe that there are other tablets on the market now (tell me if I'm wrong), but they aren't up to snuff. Nothing beats a wacom. I personally have an Intuos2 and love it to bits. I started out with a little Graphire with a 4x6 inch drawing space. Now I'm up to a 9x12, but I don't think more is necessarily better. I got along great with my Graphire. Had it for more than five years and I passed it on to its next owner still working great.

I believe the new version of the Graphire is the Bamboo? I have a couple of friends with Bamboos who really love them. They're probably the cheapest, running about $100 (again, correct me if I'm wrong).

You might be able to find used tablets on ebay that are priced less, but you'll find that tablets really tend to hold their value... because they don't seem to break.

So yeah, as much as they cost, think of it as a long-term investment~