As for peltiers, they come in sizes according to the Wattage rating, the higher the wattage, the better the cooling power. It's basically looks like a square block of metal about 3mm thick with 2 wires leading off it. One side is known as the cold plate, the other side is known as the hot plate. It basically transfers heat from the cold plate to the hot plate at an accellerated rate according to it's wattage rating. Peltiers are able to achieve sub ambient temperatures that way. BUT there must be something cooling the hot plate. An air cooled heatsink will do, but due to the immense heat transferred to the hot plate, an air cooled heatsink will not allow a chip to go sub ambient and operating at such high temperatures isnt very good for the peltier either. Usually, peltiers are used in conjunction with watercooling systems for their maximum effect.
Peltiers also use up a huge amount of electrical energy, requiring their own dedicated power supply.
I think Peltiers are not worth it due to the condensation problems that might arise from sub ambient temperatures as well as the amount of power consumed.
But u can grab them from DangerDen.com i think.