I will be spending three weeks in France is fall and while there would like to purchase a SIM card for my Droid Pro for both voice and data. Would anyone be able to give me the steps of what I need to do to make that happen? I've heard about having phone unlocked. Is that necessary, and assuming so, how is that done? Once in France is there anything I should look for in purchasing SIM card(s)? (Expected prices, certain carriers to use or not, etc.) Thanks for any help you can give!