I Googled those four words because that is what I have an interest in: it's what I like to read and what I like to write. The novel I just finished is entertaining, yet hopefully thought provoking. There is an overarching social message. It's set up to be a four-part series, with the first novel taking on the parallel between the African diaspora and what many call the Katrina diaspora. White power against people of color which is now a centuries-old theme. (There's an interesting thread in GD about the world view and how Obama being elected would be a seismic shift in how the world views the US.) The other three address ancient human conflicts (male vs. female, ancient wisdom vs. modern thought, East vs. West).
Anyway, I also see a thread here about Barbara Kingsolver. One of my favorite authors, one of my favorite people. She is a huge proponent of literature for social change. See the Bellwether Prize.
http://www.bellwetherprize.org/change.htmlI thought you might want to check out this site and any links it may provide as you peruse novels.
http://www.socialit.org/