Books and radio are a natural pairing. For example, we know from audience analysis that public radio listeners and book buyers are almost a 1-1 match. If an author finds a public or news/ talk radio audience, book sales very often follow.
If you're an author, how can you get your pieces on radio? Drop a note to firstname.lastname@example.org and ask about a radio consultation. You may not start out on the Beeb, but there are public radio stations all over the country where your voice very well might be welcome.