Below are my favorites ones from this group.
"Costuming made easy - How to make costumes from cast off clothing" by Barb Rogers really shows what can been done with thrift store stuff. This is probably the cheapest and fastest way to cobble together costumes for an amateur play.
If you were only going to own one book in this category I would recommend "Stage Costume Techniques" by Joy Spanable Emery. She covers basic clothing history, fabric choices, pattern making, how to set up a workroom and the costuming process, meaning what the costumers responsibilities are. Generally a good book. She also runs an amazing collection of home sewing patterns from the beginning of home sewing patterns at the University of Rhode Island.
It is considered a kids book, but every adult I've loaned it to has loved reading it AND has actually learned some costume history.
I looked at Amazon and there are some used copies for sale starting at $.01! Well worth it.
This should take you to Amazon.