1. Get a Windows XP (2000 should work) machine.
Turn it off. Take your locked drive, and plug the power into it, but not IDE.
2. Turn it on and boot normally. After booting, plug the IDE into the locked drive.
It's OK, it won't break anything.
3. Go into device manager and make it search for new devices.
If it doesn't find one, keep trying, until it finds your locked drive.
4. Run LiveInfo (google for it). It will tell you some stuff about EEPROMs, but what we want is the hard disk information.
Pick the locked drive from the drop-down box. It'll tell you the password.
5. Print it out, then go into DOS and run HDUNLOCK. Enter the password correctly.
Then run HDDISABL, and enter the same password. Et voila.