ok i got a t mobile mda for free (dont ask how *shifty eyes*) but they do not have any service where i live, is there a way that i can use this phone with another service provider say cingular or something like that?
Most phones that you would purchase from a cariier are "Locked." This means that they are branded and will only work with one carrier (hence, why you may get a discount on the phone).
...One may "unlock" their phone using unlocking services available on the internet ($$). This will enable you to pop in a sim card from another carrier, such as Cingular, into your phone. It will ask you for a "Unlock Code." This is the code that is calculated for you. Do some research and you will find out more.