Off on a tangent, but can I throw out an idea?
Tim Ferris in 4 hour work week book talks about using pay per click advertising to test out interest in new products.
You would probably find the book interesting and useful. I think also you'd want to do what Ferris suggests in an ethical way (as I think he himself notes...) but his idea to try selling your product first, to test the market, surely contains some possibility.