The audiobook industry is booming, yet only 5% of books ever get made into audio format. If you’ve got a background in acting, or if people have said you’ve got a voice made for the radio, you can make extra money recording audio versions of independent and popular books. Sites like ACX connect authors with audiobook performers. So, whether you’re an author looking for more ways to sell your book, or an actor/voice actor looking to make some extra income, you can sell your services online.