Chances of getting my harddrive recovered

Step 1: Stop doing anything with the computer. Anything you do will likely make the situation worse.

Step 2: How much is the data worth to you?

It sounds like your drive had a mechanical failure. In this case, your best bet for recovery is to send it off to a professional data-recovery company. This will cost you about a thousand dollars, and they probably won't be able to recover everything.

If your data isn't worth a thousand dollars, you can play around with the drive. Try running the computer in different orientations (on its side, upside-down, etc) in case the bearings work better when loaded differently. Try sticking the hard drive in the freezer (in a bag to keep moisture from condensing) for a few hours to see if differential thermal expansion frees things up. Try rotating the drive rapidly around the spindle axis to free the bearings manually. But keep in mind that the most likely outcome of doing all this is the total destruction of the drive and all data on it.

You are likely doomed. The store gurus will go over data recovery options and explain they don't fix damaged drives, they are simply going to ask about the status of your backup and whether you want them to test the operation and see if it needs to be exchanged under warranty / AppleCare.

Some things to try on dead and near dead drives include putting them on their end or sides rather than having them oriented flat - this is because the read/write heads that sit between the actual disc platters may respond better then they are held vertically by gravity rather than horizontally by their precision engineering which sounds like it;s been compromised. Give it a go, see if it sounds any better (assuming you are not using an iMac where they are are already mounted this way).

Sorry to be the bearer of bad news.