My free iBook is not visible in iBooks
How come that I can't find my iBook in the iBook store after a succesful delivery according to iTunes Producer?
Depends on how many days it is now - since you delivered the book.
Have you checked your iTuned Connect account > Manage your Books? If not check it.. it will advise the current status of your book ie orange dot and In Review or green dot means its accepted and going into the store store or , it may have a Ticket and needs corrections.
If all is well, actually appearing in teh store depends on how busy the review team are and it could vary 3 - 14 days.
In the books store search for your name or what you use a author and the book title in its catagories.