One way that you could get access to your hard drive without Windows would be to use Ubuntu(
http://www.ubuntu.com). Ubuntu is an operating system like Windows and Mac, but is free. Not only is it free but you can try it out without installing it, which is what you use inorder to access your hard drive.
1) go to
http://www.ubuntu.com/getubuntu/download and download the .iso file
2) burn the .iso onto a new CD-R
3) Insert the CD into the computer, and restart it
4) Ubuntu CD should load, don't press anything and let it start up (you don't want to accidently install it)
5) Once the desktop is loaded, you should see something that looks like a cross between windows and mac
6) On the top bar, go to "Places" and look for you hard drive
7) Once you've opened up the hard drives folder, you can drag and drop things that you want to back up on to an external hard drive or usb
Its not gonna be the easiest thing to do, but it beats paying $100-$150. Hope this helps and wasn't too confusing. Maybe someone else has an easier way.