HOw do you change a cell phone from one company to another?

Question

To make this simple, I found a Motorola Krzr Phone. It charges. All things seem to work. The Service Provider is Cricket. If i want to use this phone, but not Cricket, How do I go about changing it. Just to let you know, it does not have a SIM card.

Answer 1

You have to unlock that phone, and unlocking, as i found out yesterday, is illegal.

I wanted to do the same thing.

Answer 2

The phone DOES have a sim card.  If you can't find it, that means you have an older phone whose sim card is NOT removable.  Such phones CAN'T be switched to another carrier.