Well I managed to get my old hard drive to fit after removing the 2 screws on the side (and realizing that it didn't use the pin connectors either). It fits now, but the case on the hard drive that is supposed to be in this laptop has a tab with a hole in it to lock it in place with a screw, while the one I have in here right now doesn't. The biggest issue is that the hard drive from my old laptop (the one in here now) is running a windows vista install, and isn't activated for this laptop, and has no drivers, so it can't even connect to my network. I could likely get some drivers and make them work if I really wanted to, I guess.
I've got my brother downloading an ISO of Win7 ultimate because I can install home premium from that anyway. Of course he doesn't seem to realize that downloading that ISO takes presidence over him playing his games. So for now I'm using my stripped down gentoo-on-a-flash-drive for internet access with links.... The internet sucks in text though :S
So, If I just buy any random drive, I should be able to make it fit in here? If that's the case, then I'll get one ordered ASAP.
EDIT: I noticed that there were holes in the top of the old drive, and removed the mounting bracket from the new one and sure enough, it fits.
Of course, this is really just a hold off until I can order a new drive, because this one is kinda small, and I can get a 640GB drive for like, $70 + shipping.