I've never marketed anything here and I've sold quite a few. Nice thing about this site is that it brings the customers to your work, so you can focus more on your writing. The owners of the site work hard at bringing in new customers, which is very nice. But it couldn't hurt to do a little marketing if that's what you want to do. As for when they will sell... that's a whole other story. Basically, when the right buyer comes along, things sell. For faster sales, you might want to look into the public requests, because you know there is a buyer ready to buy articles based on those topics.