Try using the search feature found at the top of the message board, this topic has been covered a bunch!
A short explanation though, each unlock code is unique to each blackberry. It is based off of the IMEI number which is also unique. You get the unlock code from your carrier or a 3rd party unlocking service. They will provide you with steps on how to unlock, or search the forums for "unlock" and you will find it. No need to reinvent the wheel.
Did you mean the sticky topic with 58 pages of US carriers? Because, that, I have read. I called T-Mobile UK and they refuse to give me the code, which was why I posted this thread.
What 3rd party unlocking service do you recommend?