Hard Knocks Books has published a free step-by-step guide to uploading books to iTunes geared toward the novice self-publishing author. These instructions are offered free of charge.
Authors are warned of the necessity of:
° Owning a Mac computer before attempting to upload books to iTunes;
° Applying for an iTunes account via iTunes Connect (a link is provided);
° Purchasing an ISBN # from Bowker for each book being uploaded (a link provided).
You can find the guide at http://donnafasano.blogspot.com/2012/09/uploading-books-to-itunes-using-itunes.html .