Continuing with book recommendations, I would like to offer the work of sociologist, Peter L. Berger. There hasn't been an author who has influenced my thinking more than Dr. Berger. (go here for more info http://www.bu.edu/sth/faculty/staff/berger.html )
I am recommending three of his books that our related to religion.
I can say that his, The Sacred Canopy, changed my understanding of the practices of the church and challenged me as to their veracity and efficacy. Dr. Berger, in no uncertain terms -- using sociologist's tool the Sociology of Knowledge -- manages in a few hundred pages to call into question and explain sociologically everything we do on a Sunday morning. If it weren't for the little second appendix in the book, I might have given up the entire enterprise of church and church work.
I recommend A Far Glory because no other book I have read so explains and locates the culture wars more clearly than his explanation of the bifurcation of the middle-class.
And I recommend Questions of Faith because one senses Dr. Berger, at one time a Lutheran churchman, may have turned a corner and is here offering us his final considered reflection on how to have faith in the postmodern/postchristian context.