Q: Purchased audiobook wont download on iphone

Hi, sarahconte.  

Thank you for visiting Apple Support Communities.  

I would need a little more information regarding the errors or behavior you are experiencing to provide a better answer.  However, try downloading the audiobook via iTunes on your computer by checking for available downloads.  If the issue persists, you may want to report a problem with the purchase.  

Resume interrupted iTunes Store downloads

Report a problem with an item purchased from the iTunes Store, App Store, Mac App Store, or iBooks Store

-Jason H.