80mm fans to cool rack case?

[stubhead]

I just bought a 2-rackspace amp for a really good price:
SRW SM 500
They have a reputation of running hot. I have a 4-space SKB case, and I want to use one space for a power supply. I will need to mount a couple of fans inside the case for cooling. The direct AC-powered fans I've found are all 120mm, and it would work better for me to use the computer-sized 80mm fans. However, they all seem to be "3-pin" or "4-pin" powered. I have been searching my brains out trying to figure out a... what? AC to 3-pin power supply? Or something? It occurred to me that somebody may have already figured this all out, and can just point me at the stuff.

 

[Sixbender]

I've been using 80mm rack fans in my rack rigs for years. You can get one that is two-wire from about any electronics supplier. I use a 12V fan, and power it with a transformer in the rack (which also supplies power to the midi-control pedal). I mount the fan in a way that i can leave the rack lid on the back, so it forces the fan to draw through the amp (I'm using a Marshall EL84 tube amp). The amp stays very cool with this setup...normally an amp that runs pretty hot.