I just ordered a couple of fans,
http://www.directron.com/sil.html with shipping, they are $25 total, bringing my cost up to $55. If you want to see some testing of fans for noise, check out
http://www.directron.com/noise.html. I was shopping for a cheap 12 volt adapter to run the fans when I thought about all of the battery chargers I have collected from cell phones, etc. Great idea! I have a couple that are just the right size and rating. Zero cost for that one.
Today I also got the surface of my "heat sink" sanded and polished as much as I think is needed. I started with 80 grit dry wall sanding paper, which is silicon carbide paper, and it worked very well on aluminum. Then I used 150 and 320 grit to finish sand it. I should have my camera back tonight, so I will plan to take a picture and post it.