Below is a list of recommended metal detecting books. I own and have read most of them.
General Metal Detecting and coin shooting books:
The Metal Detecting Bible by Brandon Neice
Metal Detecting for the Beginner: 2nd Edition by vince migliore
How to Research for Treasure Hunting and Metal Detecting: From Lead Generation to Vetting by otto von helsing
The Urban Treasure Hunter: A Practical Handbook for Beginners by Michael Chaplan
Coin hunting ….. in depth! by dick stout
The new successful Coin Hunting by Charles Garrett
Metal Detecting – Learning How The Easy Way! by Ronald Kamrowski
Find More Silver Coinshooting Parks and Schools: Dimeman’s Detecting Tips by Robbie Morin
Cache Hunting:
Treasure Caches Can Be Found by Garrett, Charles
Water and Beach detecting:
Metal Detecting the Beach by Mark Smith
Gold Beneath the Waves: Treasure Hunting the Surf and Sand by Jim Brouwer
Other:
The Minelab Explorer & E-Trac Handbook by Andy Sabisch
A guide book of United States Coins: The Official Red Book by R.S. Yeoman