^that seems like a great answer
I dont understand these american phones but if they do work outside the US (which Jimm can vouch for) then buying a local pre-pay sim will save you a fortune.
Just to add to what Jimm said.. go into Settings, More, Mobile Networks, Access Point Names (APN) and make sure your carrier hasnt locked the ability to create a new APN (the "+" sign at the top right) :thumbup: