The only regularly updated book club hosted by National Public Radio as of August of 2015 is the Special Series--Morning Edition Book Club. The archive of books that have been reviewed in this series can be found at npr.org/series/402558323/the-morning-edition-book-club/archive.
In the Special Series--Morning Edition Book Club, a well-known writer selects the book that the club reads and then the series' listeners submit questions and comments for the selected book's author. As of August 2015, listener questions can be posted on Twitter or Facebook using #morningeditionbookclub, or listeners can post at the bottom of the page for the book club article. Some of these questions and comments are read on-air and incorporated into an interview between the book's author and a National Public Radio host. There is a month or more between episodes. The archive goes back to December 2014 and includes a total of two books.
For those interested in accessing the archive of books reviewed by National Public Radio hosts and guests that are not affiliated with the Morning Edition Book Club, this can be found at npr.org/books/archive. This selection is updated far more frequently and includes a weekly review of best selling books in hardcover and paperback editions.