Audiobook Builder is not specifically designed to distribute any audiobook content through retail channels. Though Audiobook Builder books can be sold, we are not partnered with the iTunes store for such sales or distribution.
the iTunes store and Audible do not usually handle small or individual publishers for making your audiobook available for sale. From what I can gather, the best route to take is to link up with an indie content company and have them market your materials to the various online stores. The name that keeps popping up for me is
CDBaby.com. They appear to be primarily Music on the surface, but they handle many different types of content, including audiobooks. Once you sign up with them, you submit your materials and they do most of the marketing and setup for you. They also take a small percent of the proceeds and then they pay you.
This might be a good place to start.