I love books on cd for my kids, especially for car trips as my kids tend to often get car sick from reading or watching tv so this is a great option! Right now Hautelook has a ton of books on cd here are some of my favorite selections:
Horton Hears a Who – $6.99
Ann of Green Gables – $12.99
The Lightening Thief – $12.99
Ella Enchanted – $17.99
Bunnicula Collection 1-3 – $12.99
They also have Harry Potter, Twilight, and The Magic Treehouse books. Shipping starts at $7.95. Go here to check out this sale at Hautelook.