How to Unlock Cell Phones?

So yall probably read my question about Sim card changing from a cingualr phone to a tmobile.



and most of yall said to unlock the phone.



but I want to switch back and forth between my phones.

this isn't a perment thing.

I don't know how to do that.



I have a tmobile motorloa SLVR L7.

And I want to put my cingular RAZR v3T sim card in it.



I don't know who to unlock.



please help;How to Unlock Cell Phones?
One way of doing it is going to the little %26quot;Mom and Pop%26quot; cellphone stores A lot of time they can do this for you for a fee Or you can try contacting your cell phone provider and tell them you will be traveling outside of the country and need to have the phone unlocked so you can use it overseasHow to Unlock Cell Phones?
wowHow to Unlock Cell Phones?
Cingular and Tmobile both use different sim cards and software. Who is your cell provider firstly and then secondly the phones have to be unlocked by your provider. Take it in to a store.How to Unlock Cell Phones?
its usually the last 4 digits of the cell phone number, if that doesnt work it has been changed. and thats the difficult part.