Mark, it helps to know what state you are wanting info on. If you are in Oregon " Oregon's Golden Years " by Miles F. Potter, printed in 1978 is packed full of history. For Arizona " Handbook to Arizona 1877 " by Richard J. Hinton is a good read. As for California there are many books on the history of mining. The one I like best is " Geologic Guidebook Along Highway 49-Sierran Gold Belt Bulletin 141, The Mother Lode Country " 1948 Division of Mines.
Hope this helps and good luck finding your spot to dig Gold. Ron