i ended up taking the door panel off, and taking the whole lock assembly out, removing the key, which is a VERY delicate process so take your time so the copy key will still work after you're done, and put everything back in it. you'll need some screwdrivers, needle nose plyers, and two hands.
I just changed out the lock cylinders for the doors, t-tops, and trunk on my NX2000 in half an hour. It is very easy to do. Just look for the bars that connect to the door handle inside, unplug them, then undo the two nuts and it should pop right out. Then you can work ont eh cylinder from there to get the key out.
Go to a locksmith and they will charge you 5 bucks or around that. They should be able to get it from the outside of the car and it doesn't take long. You could by a key extractor set from them or some hardware stores and do it yourself, there around 20 bucks.