Hard Drive failure

That doesn't sound good at all. Does it make any clicking or other unusual mechanical noises? If so, the less you try to use it before sending it to a professional data recovery service (if you need it), the better.
If it isn't making funny noises, it may still be mechanically sound. One possible solution is to find an identical drive (may need to use eBay) that still works, and transplant the controller board from it. Obviously, the board revision must be identical. YMMV; I've done this and completely recovered drives, and I've done it and gotten zilch.