Guiley has a knack for puting together information-packed books. This one is chock-full of useful info, which is great for gamers (like me and my friends). The backstory and descriptions of the ghosts and ghostlike creatures is great. My only complaint is that the writing is pretty dry. It reads more like a college thesis than a book written for the public. I still recommend it to everyone.
This book is an excellent reference book for the serious ghost hunter / paranormal investigator. Provides good case histories as well as "ghost stories" that can be used as examples on investigations.