Which Graphics tablet on Macbook pro ?

Have been a Mac user for a year now, as an artist I am just starting to look into buying a tablet or similar. Have not much cash to give to it, but realise that few things are cheap AND effective I want to use this with illustrator or photoshop, so it has to be reasonable quality. Have read about Wacom, smaller tabs at reasonable entry prices . . . any thoughts ? experiences ? what should I AVOID !!!
Thanks in anticipation

I've used the following on my MBP's over the past couple years...

Wacom Intuous 3
Wacom Intuous 4
Wacom Bamboo

The Intuous' are more sensitive and accurate than the Bamboo is, but the bamboo's not bad.. especially since it's pretty nicely sized for portability (and cost). The newer ones should actually be much nicer than the bamboo I've got kicking around (a couple years old now). A couple of them also come with PSe, which is kind of nice.. and I believe Sketchbook express.. (although that's free on the App Store anyway)

I really don't have any experience with any tablets other than wacom. I've stuck with them now for over a decade.

Wacom is the best of the best. I don't ever leave home without it.