Parse Feed off Cafepress.com to create Website Display

I need to create a website/process that happens as follows: Website owner creates easy updatable list of keywords, that then turn into Menu choices on the actual website. User can also type in keyword based on their choice. The feed for results would come off of [login to view URL] using some sort of system where the page fetches the info from [login to view URL] search/system based on menu keyword choices or user entered keyword choice. I'm sure there is a way for it to display and/or cache and then display. It would then display about 30 products across the page in a pleasing manner.....with price. (all fetched info from [login to view URL] search) I'd also like it to be paged, or let the user continue searching the keyword and getting results. One option someone told me once was parsing the RSS feeds, but don't know anything about these. These images/products/results also must be tagged with a special tracking # added to the end of the click through URL. This would be uploaded to my server.