Absolutely possible, but you'll need a little programming background to make it happen. I've built about 40 sites using eBay's XML feeds - here is a link to get you started:
http://developer.ebay.com/programs/affi ... eapiguide/
I did most of the coding myself, but spent $20 at rentacoder.com to get the tricky bits finished. I *really* like the XML feeds instead of javascript because the results are search engine friendly.
Here are a couple of sample sites I've setup:
I coded my sites in PHP, but you can use a variety of languages.