Here are a few books that that personally recommended for your rccommends

1. The Book of Alternative Photographic Processes by Christopher James 

This is a heavy book of almost 900 pages. Being the 3rd edition, it has the latest updated information on the various alternative photographic process including a chapter on wetplate collodion photography.  The author shares the various formulas that are required for the various processes such as cyanotype printing , kallitype printing, salt printing etc.Buy it now on Amazon

2. Chemical Pictures The Wet Plate Collodion Book: Making Ambrotypes, Tintypes & Alumitypes
by Quinn B Jacobson (Author)

Quinn B Jacobson is considered to be one of the gurus in wetplate photography.  He hosted regularly a live talk show on  wetplate and other alternative photographic processes.  This book covers everything you need to know about wet-plate collodion photography. Quinn teaches you how to make direct positive images on glass and metal plates; Ambrotypes, Tintypes, and Alumitypes.Buy it now on Amazon