There is not much on this subject, if you go to YouTube and search for "Peltier cooling" there is quite a lot on the devices but very little on PC cooling, basically if you have seen or purchased drink coolers for the car that plug into you cigarette lighter, these contain a a peltier device, it has 2 wires, just add 12v dc, one side gets hot the other freezes, they are about 1.5" x 1.5" x 1/8", you would place a heatsink on CPU that has a flat area to mount this device with a heatsink on that, then you need an electronic thermostat to switch the device on when temperature rises and off when cooled!
Here's some basic info:
http://www.heatsink-guide.com/peltier.htm