If you know how to take the door lock off, there is a number stamped on the locks. Ford are actually very cheap making keys to fit, providing you have this number. I paid £6 which is very reasonable.
You may find that the passenger door and boot are actually the original locks to the car, and the drivers and ignition have been changed due to an attempted theft. Best thing is to get the codes off the locks, and you'll then know how many keys to get cut.
Jonathan White, January 2006