The Faithful Home of the Three Stars: The First 150 Years of Beta Theta Pi, written by Peter J. Floriani, Lehigh '77, is the definitive book on the history and lore of the Beta Theta Pi Fraternity.
The Definitive Beta History Book
I had the pleasure of getting gifted this book as an active member, and read it as part of preparation for being Pledge educator. Bottom line is that this is one of the best researched and written Beta history books out there. Son of the Stars just scratches the surface by comparison (although it is a good book in and of itself). Highly recommended.