I have been teaching Crime Scene and Evidence Photography for about 24 years. Several years ago I wrote a field guide, entitled the Crime Scene and Evidence Photographer's Guide. The field guide is designed to be carried as a reference in the field, when processing crime scenes. The book is in its 2nd edition, having sold over 10,000 copies. It is used by crime scene investigators and as a text book in some college courses.
You can learn more about the book at http://www.staggspublishing.com/CSEPG.html