How are you promoting the site would be my first question, although that's nothing to do with the design. Also, if your primary aim is to get email signups, why do you have Adsense on the page? Remove the Adsense because you'll just get people clicking the ads and not signing up.
Onto the design, I've seen a lot better pages that say the same thing. Where are the graphics? The prices need to be a lot bigger, higher resolution. You need to sell this thing.