Stephen King, John Sandford, and J.K Rowling can release a 15 second ad saying-I have a new book out go buy it. They have well established brands and following. Readers know what to expect from them. Self-publish or traditional--paperback or electronic, until you reach that point you will be doing a great deal of the PR and marketing. You could have written the best book in the history of books, but until the readers know about it they can't buy it.
As a writer, producer, and editor I can give you a tool that will positively promote you book and your brand. I can't promise to make it a best seller; only the quality of your work can do that. What I will do for you is help your readers find you.
Let me help you with your marketing challenges.