Along with the physical paper-turning editions of classic books we are employing a mix of kindle and audio books to help us to achieve that goal.
Here is one option that I have found useful:
$0.99 deal with free Kindle books and those really reasonably priced audio book options whispersynced in.
An audible account is necessary.
(We use the $9.95, a year, membership)
I've also found that after purchasing the kindle book on amazon, flicking over to audible and viewing the other audio options of the title you've just purchased can bring up a range of "on sale" options.
I'm very happy to purchase a very well read audio book for $2.99 ☺