Is it clicking, or making more of a grinding noise? Can you hear/feel the drive spin up and stay spinning? Grinding likely means the read/write heads have crashed onto the platters and you are SOL. If the drive spins up and stays spinning, you may be able to recover some of the data you lost.

Disclaimer: If you do this, it is at your own risk.

Your best bet would be to make a clone of the drive, if it is still possible. Just for example: If you have a 500GB drive, try to find a blank drive of equal or (preferably) larger size, like a 750 or 1TB and attach it to your computer. Download a bootable linux disc ISO and burn to DVD (anything that can do DD, I think most linux boot discs can).
Boot the system to the linux disc and run a "sudo fdisk-l" command if you aren't already under root privileges. If you are, skip the sudo part. You should see your main drive and the drive you added. Usually they would be listed as /dev/sda, /dev/sdb, etc...
This is where it is easier if you have drives of differing sizes. The drives will show the total size. If both are 500GB, it is harder to tell which is which. But if they are different, you see how it is easier to tell the difference.
Once you have figured out which is which, run a DD command to copy one drive to another. As an example, if your main (failing) drive is listed as /dev/sda and your new drive is /dev/sdb, then you would run a command like this:
dcfldd if=/dev/sda of=/dev/sdb conv=noerror,sync
the last part will tell linux to skip the bad sectors and fill the destination with zeros where the bad sectors were instead. It may take quite a while depending on the drive health status and size. For example, I recently cloned a failed 1TB western digital green drive (garbage drive if you ask me) and it took about 4 days with all the bad sectors.

Once the clone is completed, there are several recovery utilities you can use to search for files. In my case, the MFT was part of the sectors that were lost, so I could not see file structure. I had to run searches to find and copy out the files. A little utility that I found that is pretty good at doing this is here: http://www.cgsecurity.org/wiki/TestDisk_Download The photorec 7.0 program has a lot of file types that it can search for. It runs in a DOS window, so it doesnt have any nice GUIs, but it is still fairly simple to use. Point it at the drive you want to recover from, choose the file types you want to search for, and off it goes. A little hint though, the default output directory will go to wherever you unzipped the program. So if it is on your desktop, it will output the files it recovers to your desktop. I would recommend running the program from an external drive and dump the output there. That way you arent filling up your OS drive it is running from. Hopefully you are able to recover some, if not all, of the data you lost.

Strange how what you see is correct, but then the underlying url has the colon missing i.e. a copy-paste does work. Duly bookmarked for a time when touch wood has failed.

It'd also be worthwhile adding Clonezilla Live CD to your toolkit. It has many useful features for copying a drive. There are few file-system formats that it can't copy from or to. You even have options about whether you want to do a whole disk to disk copy, copy only a particular partition, or copy to an image file (split into chunks to suit media size limits)

One other useful preventative measure is to create a compressed image file of your HDD on a semi regular basis. Clonezilla offers the option to copy an image with high levels of lossless compression to networked file systems.

PhotoRec and Testdisk can also usually be found in the additional software repositories in your favourite Linux flavour. Just fire up Synaptic or whatever package manager your flavour comes with and search for them, easiest way to install.

The progs work well, and the best thing about them all is they're free. (Usual disclaimer - I have no shares in them, just a satisfied user of all of them.)