I really need an advisor. Although I "have" one, it takes him many, many days to reply to my questions. So much for being put in touch with him by one of leaders in tech. startups....
Marketing is a broad thing - advertising is a small and limited part, especially for a cash-strapped startup. But getting people aware and interested matters. What have you done today to make more people aware of your product, or improve how you explain it to them in order to increase interest and conversion rates?
If you have some spare time, it might be good to do some reading on the business/marketing side of things. Have you read The Lean Startup? Or How to Win Friends and Influence People?