Since I can create and maintain my own web sites, I have two specifically for my writing: one (see link in my signature below) is for all my writing, including novels, sermons, essays, and other stuff. I have the whole text for everything except novels, where I offer a synopsis of each, a purchase link to Amazon.com and the ability to download sample chapters in three different WP formats: MSWord, WordPerfect, and Rich Text Format. I get some--but not a lot--of traffic for downloading chapters, but not many sales that way that I know of. Since I use amazon Associates, I can keep track of any orders from my web site, but I don't get many sales, but even one every once in a while is worth more than it costs.
My second site (
http://www.arisebeloved.com) is specifically for my new novel where I offer a synopsis and sample chapters.
I also have a book review blog with a sales link to Amazon.com for the books I review. (See blog link below.)
The main purpose of my sites, besides providing a link to Amazon.com for sales, is (hopefully) to build "name recognition" for me as a writer, which is a long-term project at best, but certainly every serious writer ought to have a personal web site for self-promotion. It's as necessary as having an email address.