Choosing the brain (computer)

I started looking for a 12V DC power supply for ATX boards. First I tried to build this myself, and I ended up with learning quite a bit about DC/DC converters (buck, flyback etc.), but no concrete solution. I found a nice National Semiconductor chip and ordered a couple of samples (which didn't work out). In the end I wasn't too thrilled building the thing myself because a couple of parts, notably the coils, seemed to be hard to come by.

So I looked at commercial solutions. There seem to be only a few products that everybody sells, ie. the PW 60 and the ITSP (?). The latter is for car use and can deal with spikes, overvoltage, and other car-specific stuff that I don't need.