HardHeadCase, here are the items he has listed on ebay currently:
eBay Seller: hotaudio40: Home Audio, Portable Audio Video items on eBay.com
He's got 3 main HP amps from what I've seen. A USB dac/amp, HP amp and HP amp/preamp. He uses a couple of different opamps in these for variety I guess. These are no frills products, designed for maximum sound quality at a reasonable price without the bells and whistles. I got the USB dac a few weeks ago and that was much better then my audigy 2, particularly utilizing asio4all plugin in foobar. This past week I got the opa2134 version amp and it makes even my cheap pioneer dvd player sound pretty damn good. I suppose it depends on the headphones as well but both my grado sr60 and senn 580's sound good. You can see he offers some for bid and others for buy it now or best offer. In my case he accepted a much lower offer and you can contact him and work something out, he's very easy going and informative about his products. He's got good feedback on ebay too.