I am not a fan of organized religion, but I like to read about them while trying to gain an understanding about these different aspects. One of the most interesting religions is Buddhism, and I believe that Zen Buddhism is a good way to try to understand Buddhism.
This is a very comprehensive overview of what Zen Buddhism is, its history, beliefs, everyday practice, and a good how-to-guide. For such a short book it gives the insights you need, and I especially enjoyed the way it was written to the everyday person who might be curious about Buddhism, but might for example think it is "too out there for me". Recommended!