I get nearly all the traffic from Google. AdWords never worked for me. For a few months I got a lot of great traffic from Cake Central. They have a cupcake forum [1] which is hyper-relavent to my site. Also, I reviewed myself [2] in their reviews section, and it sat in their sidebar feed, getting the placement of a $1000/mo ad, until it fell off.
[1] http://cakecentral.com/cake-decorating-forum-33.html [2] http://cakecentral.com/products/cupcake-wrapper-creator/revi...