I do not know much about cellphones or mobile technology. I know what I read and I have a basic TracPhone for emergencies, but mobile technology is the emerging trend in communications and I know this. Obviously, it has been around a long time, but the new iPhones, Blackberries, and the like are easily the new wave of advanced communications.
Like I say, I know what I have read and seen on TV and I have obviously heard about how the newer phones do not allow you to do much without their proprietary standards kept in-place. Cell Phone Unlocking has become a sort-of underground technological movement - the new phase of practical Cyberpunk, I suppose. And while there are tons of sites with tricks and tips on how to unlock your phone and tweak it, hack it, and crack it, you spent a few hundred bucks on the thing, so you are absolutely right to be wary of the information you find and careful before you proceed.
But make sure to follow the link above for more information on how to unlock your phone and access more functions. But, of course, make sure you read everything first and know what you are getting into before you make the big leap into DIY... mobile destruction.