82888 Link Exchange

Looking for someone that can create a hidden links exchange. This is like a banner exchange without the banners, grouping similar sites and creating hidden links on their sites of the other sites in the exchange. Basically users would sign up to the exchange and pay through worldpay for 1 years subscription. They would choose a category and be given a bit of code to include on their site (php or javascript)which would pull the code from my server listing all the sites in their category. It could even limit it to 20 sites etc, the links would be on a 1x1 pixel image. The search engines would like this because similar sites are linking, site owners get more traffic, links are hidden etc. I saw a similar site [login to view URL] (offline) only the problem was they relied on you having php pages to include the links from their server, and those that did not had to cut and paste the links to their server. I hope this makes sense?