When I plug in my PS3 Sixaxis controller, it installs the drivers, but I can't get it to work in any games. I want to be able to use it in modern games and in emu programs like ZSNES. Is there a profiler program I can get ahold of to do this?

Do you have the 64-bit version of Windows 7? By default it can only use "signed' drivers. You can work around this in various ways (here's one of them) that all boil down to disabling driver signing enforcement either temporarily or permanently (depending on your preference).
EDIT: if you're not sure whether you have 32- or 64-bit Windows, open the start menu, right click Computer and choose properties. The "System type" field holds the answer. If you have a 32-bit operating system the driver signing restriction does not apply--so you don't have to do any fancy steps to get around it--and your problem must lie elsewhere.
EDIT2: also note that some PS3 controller drivers specifically work over bluetooth, and if you don't have bluetooth for your PC they won't work at all.

well that MotionInJoy software seems to work well, I hope they keep updating it.