Thanks for your question. I also saw your post about the similarities between The Help and The Space Between Us in The Help forum, and hope to get back there to respond sometime soon (as you're right, there are a number of similarities and I hadn't thought to compare them before).
With regard to your question about resources, have you considered looking through BookBrowse's themed categories for ideas? Click on the "Find a Book" option in the menu and then select a section from the drop down menu. For example, if you were interested in comparing books that explore "coming of age" you could explore that section under "Themes", or if you were interested in a particular time period or setting you could find books to match. With over 120 themed categories there's a lot to explore.
You can dig down even more specifically using the Book Finder tool - also under "Find a Book" - which allows you to search for books by two criteria, e.g. by a specific time period and a theme, or by setting and time period, and so forth. The results will display both fiction and non fiction - so, for example, you might decide you want to read about India, and could pick one fiction and one nonfiction read.
The best thing is that every book that will show in these results is a book that we've shortlisted for recommendation at some point over the past 12 years, so that you won't have to wade through thousands of "also rans" to find the books that are worthwhile. And because we back every book recommendation with an excerpt, and more than likely a reading guide and/or interview, so you'll have a lot of information at your fingertips to decide which you think are right for your group.
What many book clubs do is one person will search BookBrowse and then send links to their friends in the group to check out the books that look of interest. Only members can BookBrowse by all these additional parameters such as time period, place and theme, but everyone can view the individual books including excerpts.
As for background material, click on BookBrowse's review of any specific book to read the review and a back-story, which will be about something related to that particular book - as there's a good chance the "Beyond The Book" feature will provide interesting reading in itself, and links to further resources.
Last thought - if you are only interested in books with reading guides, go to http://www.bookbrowse.com/reading_guides/genre/ to browse books by theme which have reading guides.
Hope this helps.