13. The Revealers by Doug Wilhelm
14. Wintergirls by Laurie Halse Anderson
Both of these books tackle pretty serious topics. The Revealers was clever; a book I didn't like much at the beginning, but it developed into an interesting story. It includes technology though, and I wonder what middle grade readers think of it, since it was published in 2003, before the huge popularity of Facebook, etc.
Where do you hear about great books? I find out about many of them at my local library, where one of the librarians writes short recommendations and clips them onto the covers of the books. I also find books through my writing group, blog mentions and newspaper/media reviews.