If you are trying to drive traffic to a simple 1 or 2 page sales site then chances are you may not get much traffic from the search engines because of the lack of content. One way around this is to build a content site by using articles on the same topic as the product you are selling. Get articles from directories or write some of your own. Then link to your sales site from your content site.
Lisa Santos: You can have everything you want in life if you will just help enough other people get what they want.- Ziglar