Here I’ve listed a number of books that make for good reading on purple martins, however; I will add one thing. Some of them have been around for awhile and the information as far as housing requirements is a little outdated, so you’ll just have to use some common sense when reading them and apply the newer standards for keeping martins and everything will be just fine.
Martin Book, by Donald and Lillian Stokes & Justin Brown. One of the best books that I've read on the hobby of keeping Purple
Martins. This is the complete guide to attracting and housing Purple
How to Attract Birds, by Ortho Books
What You Should Know About Purple Martins, by J.L. Wade, The Nature Society, Griggsville, IL 62340
Attracting Purple Martins, also by J.L. Wade,
The Purple Martin, by R.B. Layton, Nature Book Publishers, P.O. Box 115, Valley Lee, MD 20692
Enjoying Purple Martins More, by Richard A Wolinski
How To Control Sparrows, by Don Grussing
Purple Martin Story, by Rebecca Dellinger A new book, targeting the younger generations.
America's Neighborhood Bats, By Merlin D. Tuttle. Since I have a bat house and know how much these fury little critters love night time insects, I just couldn't resist putting one book about them here also.