|It's probably possible to retrieve any non-corrupted data from a bad hard drive--it just depends on how much you're willing to spend. Yeah, a shop can probably tell you what it'd cost.|
But first check that the drive's data cable is in good condition and tightly connected on both ends. Check its power connection also. Sometimes the contacts get flared out and don't make a good connection.
Check that the drive is properly identified in cmos/bios setup.
I've never done it but many people swear that putting a drive in the freezer to really cool it off and then connecting it up will give it a little more life--enough to copy necessary stuff to another drive or cd-r.
You're not really green until you're soylent green.