WELCOME!! As the others said, The Chip Rack is the main book on Nevada chips, however doesnt have pictures. The numbers attached to each chip is now the standard id number (TCR#) The most useful place that i have come accross for pictures is our own Geg Susong's TheChipGuide.com If its a chip from a sanctioned USA casino...theres a picture. Greg has done an amazing job, and i know has spent more then a total of 27 hours creating and updating this fabulous resource.

Another very good book is Archie Blacks book on Atlantic City chips and tokens. Archie has pictures of all entries (which i find extremely important in a chip guide) The Gaming Table is also a good book for the illegal casinos and card rooms.
There are others as well...too many to name. There are books and guides on illegal casinos in new orleans, galveston, colorado, aruba, etc.