I looked through your website, possibly it's due to your pricing structure. Try introducing a monthly payment instead of on an annual basis.
Did people have sufficient time to test out your trial? What about a 14days trial instead of 7 days? 7days is too short to convince someone of your service.
Instead of just tracking hits, try offering more. I personally would like to be able to know out of all those clicks, how many were converted to sales. So far, I've only come across a website that offers this feature.
Finally, when you say not many who tried out the trial is converting to paid customers, have you analyze the industry ratio of conversion? Ask your trial customers why they did not sign up for your paid service, and send them a bonus or a free gift as an incentive to help you out in your survey.
Melvin Ng
'How-To Create Your Own Million Dollar Information Product'
http://www.internetbizresources.com