Time Machine stopped backing up my iPhoto library a year ago, lost all photos
This sounds like somehow your iPhoto Library has moved. If you hold down ALT when you click to start iPhoto, the library management dialog comes up. This will tell you where iPhoto is currently located. If you somehow had access to your old HDD, you could see where this was located.

Obviously iPhoto doesn't work without a library, so the library has to be somewhere. I would certainly dig a little to see if you could find it. 



 Unfortunately, I haven't worked with HDD recovery at all. I do know there are companies that do this. You could potentially send it it. I'll update or comment if I do find something.