AT&T Blackberry info

Hello everyone. I'm living in Central Europe and love using my Blackberry. But I will be in the US more and more and want to have one there as well. What do you recommend? Seems AT&T is the only way to go if I want GSM service but I'm totally confused by the plans they offer. Does anyone have any words of wisdom on this? What's the most typical plan? I won't be on a designated BB server so I'm afraid of the data plans, roaming charges etc.

Any insight will be greatly appreciated.

Thanks.

T-mobile is also another GSM carrier here in the states.

You will need a basic voice plan, as well as a BIS specific plan. I believe the cheapest they offer for BIS now is 200mb a month for 15$. Voice plan is your choosing, not sure how much you'll make calls.
I believe all voice/data plans are national now so there's no roaming in the continuous 48 states. Calling outside the states in a totally other story.