Dick Staub has blazed a trail on a journey that is very similar to the one that I find myself in. With my own understanding of how to interact with the culture around me in many ways... underdeveloped due to some of the teachings from some of the churches I grew up in, I immediately appreciated the "back-to-basics" format that Staub uses in Too Christian, Too Pagan.
It reads much like a primer for the culturally ignorant, with scripture and examples throughout the book that drive home his points that as followers of Jesus we need to be actively involved in the world around us--reading the books, listening to the music, watching the movies--all with discernment--and foremost learning to love people the way Jesus does. At the same time, however, we must be careful to not let our thinking be conformed to the philosophy of the world in which we find ourselves. This dual citizenship is the heart of the gospel, and is why if you are following Jesus as you should, you will seem "Too pagan" for your Christian friends, but at the same time, "Too Christian" for the world at large.
This is certainly not the most detailed and scholarly book written on the subject, but I highly recommend it to fellow believers. It's fast paced, light-hearted, and easy to read, and covers an important subject matter from a stand point that we don't hear often enough.