I used to do data recovery from "dead" hard drives. Many times it's a software issue that is easily remedied. A file gets hosed on the drive that keeps track of everything. Restore it, and you're good.
Many times it was just an operating system failure. All of the data was still intact. Again, either restore the OS, or put the drive into another machine as a 2nd drive and copy the data to the host drive.
Physical hardware problems are a different animal. Surprisingly, I had great success over the years putting the dead hard drive into a plastic container and putting it in a freezer overnight. Then I'd pop it out of the freezer, install it as a 2nd drive in another computer, and it would spin up one last time. Don't turn it off or let it sleep. I'd copy all of the files to the host computer. Worked about 75% of the time on IDE drives.
My most satisfying experience was this:
A woman at my job had all of her wedding and 1st child's birth on her PC. That's the only place they were. The PC stopped working. She took it to Geek Squad at Best Buy. They told her it was toast. She was in tears. I overheard her talking to a coworker about it. I asked her if I could take a look at it? (I was in I.T. for 30 years, so I'm skeptical of big box repair shops). She brought it in the next day. I pulled the disk, put it into another PC, and ran a program from Stellar Phoenix. It found everything. I burnt it to DVD and gave it to her. She gave me a fruit basket, candy, and a gift card. Her husband thanked me as well.
So don't give up on that dead drive. Buy a new PC, and keep the old drive and attempt to figure out what's wrong with it. Hardware or Software. I'd say of the hundreds that I did over the years, I only failed a handful of times.