Great Books Foundation - an independent, nonprofit educational organization that creates reading and discussion programs for students and adults
National Reading Group Month Great Group Reads - launched in October 2007 by the Women’s National Book Association
Reading Group Choices - partners with publishers, independent bookstores, public libraries, and authors to develop resources to enhance the shared reading group experience
NEA Big Read Books - selections by the National Endowment for the Arts
The Booklist Reader Book Groups - regular series of blog posts on book club suggestions, author interviews and more
Book Club Central -- the best in contemporary fiction and nonfiction from BookBrowse
Reading Group Guides - from The Book Report Network, a group of Internet sites about books and authors for a large and devoted community of booklovers since 1996
Also check out NoveList Plus: under Quick Links at the top, look for Book Club Resources like Book Discussion Guides for over 650 titles, as well as feature articles on starting a new club or re-energizing a long term club.