Basic Private Investigation: A Guide to Business Organization, Management, and Basic Investigative Skills for...Apr 4 2011by William F. Blake
Process of Investigation: Concepts and Strategies for Investigators in the Private SectorMay 15 2006by Charles A. Sennewald and John Tsukayama
How to Open & Operate a Financially Successful Private Investigation Business: With Companion CD-ROMJan 30 2011by Michael Cavallaro
The Private Investigator's Instant Success SecretsMar 31 2009by Martin Day
The Like Switch: An Ex-FBI Agent's Guide to Influencing, Attracting, and Winning People OverJan 20 2015by Jack Schafer PhD and Ph.D. Marvin Karlins Ph.D.
Career Diary of a Private Investigator: Gardner's Guide SeriesSep 1 2008by David Laffler