If your HDD (Hard Disk Drive) truly is done (should this ever happen again), then purchase another HDD (equivalent to the gig size of yours, or you can even buy multiple cheap ones), set the jumper pegs on the back of it to master by following it's jumper diagram, then take your "bad" HDD, set the jumpers on that one to secondary master OR slave (you may have to reboot, go into system BIOS, and then find your boot configuration option in order to get it to detect the new HDD, as well as your bad one as a follow-up). And try variations of this option using the new HDD as your primary (By variations of this option, I mean boot your bad disk as a slave drive, boot it up, go to BIOS/CMOS, and see if you can get your bad HDD to detect. If it doesn't do it under slave, try switching it to secondary master and then do the same).
Note: Upon purchasing a new HDD, be sure that your computer's motherboard/power supply is compatible with it. Does the inside (in most cases, the base) of your motherboard have a thick, flat, red cable that connects to the back of your hard drive? It looks like the cable in this image:http://pc-level.com/wp-content/uploads/2010/01/sata-cable.jpg
If so, your HDD is a SATA (Serial ATA) compatible HDD. (SOMETIMES the cable WILL vary in color, but it's always thicker and flatter than the other plug-ins on the back of your hard drive. In most cases, there will only be one more, which connects to the power box. This is what powers your hard drive, and is from the box in the back of your computer's interior. This box is called the power supply box. All of the plug endings that come from the power supply box will be black, white, or clear plastic plugs with multi-colored cords feeding into them. Many of the plug endings MAY have the text print of P-- and then whatever number plug that certain plug ending is).
If you are using a laptop, then your SATA cable becomes PETA instead.
If you don't see any thick, flat wire that connects to the back of your hard drive, then you have an IDE (Integrated Drive Electronics) HDD. The cable that connects to the back of an IDE HDD will look like this: http://www.pcguide.com/ref/hdd/if/ide/z_000553idecable80.jpg

When purchasing a new HDD, be sure that it is compatible with your other HDD (whether it's an IDE, PETA or SATA).
Anyway, back to the subject. Once your "bad" HDD is finally detected, you can access it through your primary, or new HDD. IF you had any data on your old HDD, you can go into your "My Computer" section, and retrieve your data from that HDD, and copy/back it up to your primary HDD.
Another note: It is best to have both hard drives running under the same operating system, whether it's Windows XP, Office, 2000, Vista, or Windows 7 etc. Otherwise, if you DON'T use the same OS (Operating System) you may encounter a partition conflict that will prevent your HDD from being detected in ANY way, unless you install the same OS that the old HDD had onto the new one as well.
References/resources: I'm a computer tech. :)