Updated 7/10/15 with insights from Themis-Athena who showed me how to add the shelve it button.
Ninety-nine percent of the books I add to my bookshelf are audio editions and I have found that it is almost always impossible to find the edition I am listening to among the editions of a given title (many times because the narrator is listed as an author). In fact, I have stopped even trying to peruse the "book page" for my edition and now have my own process for finding exactly the edition for my book. The fact that I must go through this arcane process each time I add a title is annoying, to say the least.
Here's how I do it. The goal is to find the ISBN for my title I go to my Audible library page and find the book I want to add to BL bookshelf and click on the title. That takes me to the Audible page for that book. Audible doesn't include the ISBN among the bits of data it does share, so I'm not done yet. I scroll down to the reviews and click on the tab for Amazon reviews. The goal is now to get to the Amazon page for my edition, which I now accomplish by clicking on the link the link that says "xx customer reviews" to get to the the Amazon website page showing just the reviews and then click on the title of the book to get me to the book page. There I check to make sure that I've gotten the Audio edition and then scroll down to find the ISBN. I copy the ISBN and then return to BookLikes (don't worry, I work in tabs so it is just one click to get back to my bookshelf). I paste in the ISBN which takes me to the book page for my edition. After checking that I have the Audible edition, I can then click the "Shelve it" button that I have added to my browser toolbar and I am taken back to BookLikes and the book page for the book I am adding. Once there I submit edits to the BL Librarians to make sure that the narrator is listed as narrator and not author and then request that the audio edition be linked with the other editions of the title before I add the title to my bookshelf.
To add the Shelve it button to your browser toolbar, go to your BL bookshelf and click on the book beside the i. The Shelve it button does not work from Audible; I tried.
Well, at least I've found this way of adding new titles because before I was settling for just any edition of the book just so I could add the title to my shelf. Now I am slowly going back and getting the correct audio editions--because at 5-10 minutes per book, it is just to tedious and time consuming to do it in one sitting!!
Thank you all for listening while I dump my bucket and thank you Themis-Athena for the helpful information.