For example, here is the page for the Topaz GSM unlocker:
http://forum.xda-developers.com/showthread.php?t=520312
THIS IS NOT THE RHODIUM UNLOCKER!!!
I am just trying to give you an example of their license and instructions. It is tied to the individual, but assuming you just broke/replaced the phone I'm sure they'd be happy to help. They simply don't want people making a service out of unlocking phones using their software and hard work.