I agree with RDH that The Blue Book is a great quick reference to research relative values and model differences for guns which you have no specific volume. I use mine all the time.
Having said that, Don is absolutely correct that it's way overpriced and it's actual valuations are a year old the day the new book is released, they are worthless. These days the only way to get a good idea of value is to do searches of completed auctions on internet auctions sites.
I still use my 1995 edition of the Blue Book, I just ignore the actual values listed, I'm only interested in how they relate to each other. Older Blue Books are available at gun shows, flea markets and book sales. Right now there's a 1999 edition on eBay for less than $5, shipped. It's all you'll need.
