Yes, you can add audiobook editions to your site. If you'd like to add it as a purchase option in the book's listing, be sure to retrieve the link to your audiobook, copy it, and paste it as a new Retailer option within the sitebuilder. Learn more.
If you'd like to add the audiobook as a separate book entry, log in to your editor and go to Books. Click 'Add+' and enter the ISBN or insert the details manually. Learn more.
Learn more about setting up your books on your website here!