Spyware? – auto pop-up porn

Well, this is interesting. It is only happening on my home computer and I cannot find it anywhere. Whenever I start IE 6.0 within the first 5 click I automatically am directed to the same porn pages. I have used ad-aware, and a couple of other products to catch spyware and ads and it does not find it. I have manually searched my registry and also cannot find the reason why I keep getting pop-up porn. Do you know of a utility to find where this is on my computer and way to keep it from coming back? I have also rid my computer of the cookies and temp internet files and it still keeps coming back. Please HELP!