I called T-mobile in the US today as well (thanks to a tip from a kind WebmasterWorld member). Seems like I can pick up a sim card that'll fit into my cell phone that'll give me talk and text with some sort of data plan. Then I'll just use my phone as a hotspot for my laptop. I'll figure out specifics when I get there.
I'm actually not one that cares a bunch about technology, but gosh, this is pretty cool. Fly in from out of country,drop in a chip and boom I've got a cell phone number in the US and can surf the internet from my laptop via my phone - all at high speed.
I think that's the way to do it. My laptop doesnt' take a sim card. Actually, maybe it does - I've got a beast this time and it does everything including apparently 3d.