I have a site that sells a Spanish video course which I designed myself. After a year or so of selling, it has plateaued at about 200 visitors a day and about 2 or 3 sales ($17.99 per sale). 90% of visitors are from youtube where I put sample videos. I've tried other social media, but without much success. Adwords is too expensive per click for this sector.
Any ideas how to move things on a get more traffic?