Well you'll need to make sure you blackberry and quad band so it can recieve signals here.

 And the most important question is Did you one that is unlocked?

 Because simply by asking your question I can assume you don't have the skills to hack the software the phone companies add to the phone that makes sure you only use their survice.  You could always find someone here that can unlock it for you, but that's putting faith in someone not to permently damage your phone or add any "fun" little software to your phone while they are at it.