A self published book is a way to get published more easily. However, it also makes it much more complicated to sell the resulting books. They must be sold by the writer in order to make back the book publishing costs and to find an audience. Without a publisher to back the writer, the he must handle the publicity and networking by himself.
Start by writing and submitting a press release that covers the release of your book and its main topic. The press release should be sent to mainstream newspapers as well as any publication that is associated with the book's topic. That includes trade magazines as well as ones that review new books.
Get your book listed for sale online. Once the book has been published, it will have an international standard book number. This ISBN allows you to sell it anywhere in the world that will accept the book as inventory. Get the book listed on Amazon.com by submitting the book's ISBN to the site after joining the Amazon.com Advantage program.
Hit the pavement. Go out and meet local booksellers and persuade them to stock your book. Offer to hold a book signing at the bookstore to help convince them to stock your book. Send press releases to publicize each book signing.
Try to get on local television. This will prompt local viewers to look up your book on Amazon or in the local books stores. Local TV channels usually have some type of morning show that will welcome local guests. If there is a cable access channel in your area, utilize that for appearances as well.