If you have some library books to return to Tanglewood’s (new! improved!) library, you can bring them up to the clubhouse and leave them on the bench by the main door. Billie will pick them up and bring them inside. Obviously, don’t do this on a weekend.
Or pass them on to your friends who weren’t fast enough to get a dozen or more books before the library was locked. Just so they end up back in the library eventually.