Wow... from that perspective, there isn't much room for success, is there?
A business plan is not magical, nor is it full of "bull shiitake" as Guy Kawasaki calls it. The investor knows more about money than you do, and anything you try to snow him with will make you look dopey. He does this stuff for a living. You don't.
So the first thing to do is be open and honest.
Try looking at the problem from the Investor's side: I'm an Investor. I have $1000. I will give it to you if you can show me a credible plan to make it $2000 in 3 months. (Insert whatever numbers you want. Just realize that investors want short-term results. Three $10,000 investments that pay 20% in 3 months are much easier to get than one check for $30,000 that pays 30% in 6 months.)
You actually know how to deliver that value, whether you realize it or not.
You already have a product, so you can demonstrate how real world users make use of your product, and you have some stats that you can show.
You also know what Big Question you are trying to answer. Therefore you can do research for how many people are looking for the answer to that Big Question, what kind of people they are, and what fraction of them might reasonably use your product.
I'd suggest you read Guy Kawasaki's latest book, Reality Check. It really is the no bull-shiitake guide for how to present your product to investors, done in plain old irreverent English.
Side Note
A little over 10 years ago, I also developed an opt-in advertising system like yours. I called it "AdChoice.com".
Unfortunately, I was about 11 years ahead of my time (it seems), and nobody believed:
- companies would allow their employees to have access to the internet from work,
- people would ever want to choose who to receive advertising from,
- everyone thought blasting ads at people via email was going to be the "tv advertising" model of the Internet.
Ah well. That's what I get for being from the future!

