For me the best AND most cost-effective way has been through Facebook for online marketing. 4TH personal is free and grows from a sphere of influence to word of mouth and so on. In addition if you have a Facebook business page you can boost ad posts for very little compared to other marketing avenues out there now. Prices are said to surely rise soon but for now you can target your own preferred market and reach 10s of 1000s of people for less than 100.00 a post.