This is one of the sites that is hard to beat for authors. It has a great community of people who are constantly looking out for each other and helping bring everyone up. I've learned more from participating on KBoards than anywhere else.
There are a lot of people using this website, and some of them are making a lot of money using advertising. Many are friendly, some are competitive, and the important thing to note is that there are smaller sub-communities hidden here for every possible niche. One great thing about this compared to some places is that there are a lot more readers here supporting authors than at other places (for example, on WriteOn it's all for workshopping, so basically everyone there is an author).
Basically, you post a story and then you promote it. It is as simple as that. People can post comments and give you feedback about it, but for actually setting up an account all you need to do is input a little bit of information, post your content and a cover, and let things go from there.
Additional Things to Do
Check it out for yourself!