2. I think that you will need to improve your landing page to boost your conversion rate. This might help: http://unbounce.com/landing-page-examples/built-using-unboun... Additionally, if you could have some sort of short working demo on the website that should increase conversion. These guys do that process very well: http://www.memrise.com/welcome/
3. If you have exhausted your family and friends route, you could try marketing to people who have tried to learn to touchtype online, but given up. Your USP is about not playing gimmicky games, but about learning to touchtype WHILST you are using your computer like you normally would (which I like).
4. A well targeted Reddit ad might go down well...
Until release if was about development, and it is suddenly about marketing. Predictably so, but still caught me as a surprise. These look like good pointers.