Has anyone paid to have their iphone unlocked the same day?

I have an old iphone 3gs that's in great shape. I'd like to unlock it from ATT so someone buying it can use it on TMobile. I put an unlock request in to ATT back on Dec 29 and it's still pending. Has anyone paid to have their phone unlocked online? I've seen a few sites that only charge around $5 to unlock. Are these legitimate? I don't have to unlock it - I know the IMEI is good to use currently with an at and t sim card, I just figured I could sell it quicker being unlocked.

I wouldn't trust those sites. Try to call Tmobile and ask. It is in their interest to help you!