If you can't turn the key at all, you have got to drill the pin out. Not fun.

We preach and preach at people: Fix this before you have an issue! Now, when mine locked up, I had the car towed home and by the time I got it home, it turned. IF you get it to turn, DO NOT REMOVE THE KEY UNTIL YOU FIX IT. Removing the key is what sends the cam into place and that is where it locks up.