You can try Audible from Amazon free for 30 days. Included with your free trial is your choice of 2 audio books. The books are yours to keep, even after you cancel. You can cancel your membership at any time (but if you cancel before selecting both books you lose your freebies).
If you continue on with your membership, the price is $14.95 per month with one audio book included free each month and additional books at 30% off.
Note: This price was valid as of March 28, 2017 at 7:10am. The price can change at any time, so please check carefully before completing your purchase.