According to a survey of nearly 200 libraries in 30 states, about half of responding libraries produced ten or more events (including book clubs, speaker series, and author events) each year.
Your neighborhood branch library might be the perfect place to attend or host an author event.

The Humble Neighborhood Library: Why It Should Be Part of Your Book-Enthusiasm-Generating Plan | Jane Friedman
Since most readers don’t have an independent bookstore in their neighborhood, public libraries can be an ideal spot for author events.