I don't see why you couldn't do it, but it's not cheap. The car would have to be brought up (or down, depending on how you look at it) to U.S. standards. I guess you'd have to change the headlights, install a governor, and do something about emissions...and probably some other stuff, too. The duty would be 2.5% (not sure if they calculate that by purchase price or fair market value), but with the compact you would be able to forego the gas guzzler tax. Don't know how much freight would run you.
This page has some good info:
http://www.customs.ustreas.gov/imp-e...mal/car.htm#DE BTW, I agree, they're nice-looking cars. I feel a little slighted that they're not available to us. The sad thing is, I guess the discontinuation of the ti in the U.S. proves that a majority of Bimmer drivers are more concerned with image than with driving a beautifully handling, well-made car that in our case, just happens to be a hatchback.