What are some good sites to publish my books?

I've written two fantasy novels and want to publish them as ebooks where I can make a profit. There are sites such as feedbooks where I can publish them. However, I don't make money from them since these are free books. Does Amazon or Barnes and Noble allow you to sell ebooks through them? If you have experience with selling ebooks, let me know what works for you. I would rather use a site than try to do everything on my own, because it would seem to be very time consuming.