I would check out the books by John Spalding and Dick Dobbins. With a little searching, I am sure that they can be bought much cheaper than what they are listed for on Amazon.
http://www.amazon.com/s/ref=ntt_athr...20E%20Spalding
http://www.amazon.com/Grand-Minor-Le.../dp/0942627539
http://www.amazon.com/Nuggets-Diamon.../dp/0942627008
I would also go through McFarland's website and search for PCL books. I know that they have published at least a couple.
http://www.mcfarlandpub.com/searches...ure%2FBaseball