I'd say Bamboo as well. I don't know how much they cost but I was lucky enough to be given one by a friend as a hand-me-down. I'm not sure if it would be worth asking on these forums if anyone has an old one they don't use any more/upgraded from they would be happy to send to you for a reduced price/with you paying postage costs/something like that?
First ask your self, do I want to do this proffesionally, or just doodle for a living? Or am I beginner or advance? Ask alot of questions and try answering them.
It matters because if you get the intuos, you could get a good surface area, but you may not even use all the buttons. You like bamboo because its cheapest and afordable, but the surface area is small.
Generally, tablets don't matter too much, other then if its compatible with the program your using (which it probably is since from vista and onward, windows supports tablets anyway), sometimes hardware reliability, and most importantaly, if the resolution is about the same as the screen. Meaning, the surface, should proportionally as wide and talked the screen. Hardware reliability, means if the product has customer support, doesn't spazz like crazy, etc.
Wacom tend to be the standard since it has all three and comes in several sizes.
i would recommend AT LEAST intuos. bamboo is great but if you're serious about art, youll quickly outgrow it and realize all the functions (sensitivity!) you're missing that the intuos has to offer. at least that's what my friend's dad says. and he works at pixar, so i take it as fact.
Get the Intuos5 (size M, with or without the touch features) and you'll fall deep in love with it. This thing is so brilliant, so genious you can't really hold yourself from CREATING stuff with it. It's so responsive and precise (2k pressure levels baby) that you'll be blown away! The tablet itself is pure matte black, made of quality materials (looks like something you'd find from Batman's arsenal). It's a real monster of a tablet.
Definitely go with a Wacom Bamboo tablet. I got my first one years ago, and it only just broke the other day. Stick with something under 100 bucks--you don't necessarily need a large drawing surface. Intuos tablets are too expensive, no matter how professional you are.