of making a pile of money from a website. I don't know why, because there's really nothing to say that you should have any more chance of doing it on a website than in any other area of commerce.
Nobody is going to pay you to advertise on your site unless you can show audited traffic statistics, and good ones at that. Auditing a site's traffic involves a third-party company doing a traffic analysis over a period of time - a month at least. Then you'll have a rating to show potential advertisers. Don't even think about it unless you are getting many thousands of page requests a month.
If you're selling something you'll be in competition with thousands of others, all in the same business as you, and all pitching to the same market. The Internet is a hard place in which to trade - site vistors can afford to be picky, and can look at dozens of competitors in the space of a couple of hours, all from the comfort of their chair.
Concentrate on developing something that gets a lot of traffic (which is very difficult to do anyway) and then think about advertisers.