I have almost the exact same question, except I mistakenly sold my phone before doing the unlocking. Now the guy I sold it to needs to get it working on a nonAT&T network. He has a sim card.
Can anyone confirm a way to get CM11 (nightly in late July) unlocked? I don't have to revert him to stock 2.1 to unlock do I? From what I read, I don't want this guy to keep trying, as it may become unlockable after a five or so different attempts. Is this still true?
Obviously, I'd prefer free. This guy is seriously unhelpful with providing his comfort level or understanding of root/brick/unlock, etc.
e-unlocker.com is one site I found. Is this legit?