So I have to ask.. Since the 8830 runs off of CDMA and GSM technology (When your overseas); couldn't you hypothetically unlock the phone to be used with American GSM bands? Or does it only have a European GSM Radio?

It's foreign GSM only, doesn't work with US GSM.

Hypothetically, yes. Factually no.

It won't work on North American GSM networks.

Put another way, North American GSM runs on the 850 and 1900 MHz bands. The rest of the world is on 900 and 1800 MHz. The 8830 only has 900/1800 radio frequencies on it.