Carl's Adult Books. It's not a retail site like Amazon or Smashwords but a place where erotica authors can list their books.
So what, you might ask. Well, Amazon is huge and finding books there is tough, especially if your tastes aren't sanctioned by the retailer and filtered. The other retailer's search engines leave much to be desired. Honestly, most books are found by accident or by those with the patience to learn to navigate the search engine.
Carl's is nothing but books and all of those are erotica by some of the biggest names in the business. Besides Carl's books, you'll find Virginia Wade, Cheri Verset and Saffron Sands along with many others, including yours truly, and the list is growing every day. From Bigfoot to daddy/daughter to billionaire's to t-girls, you'll find what you want and more. I highly recommend you check it out!