[David Berkowitz]

I think the actual name of the Blue Book is "Blue Book of Gun Values" by S. P. Fjestad.
It wil give you prices based on condition and you really do need some experience to determine their definations and how it relates to your specific firearm.
Prices at gun shops will also vary from one part of the country to another. I think your best bet is go to the sites listed by Fernando, find your firearm or one similar, then do the completed auction search.
The first buyer will lose money due to depreciation but each subsequent buy should not, as long as the condition and desirabilty does not change.
Good luck.
OK, you didn't ask for the advise, but here it comes. Unless you made a really poor choice initially and purchased firearms of questionable quality, you will probably regrete at some point selling what you have. Save your money until you can buyu what you want. I try to buy used when I can, if the firearm is in really good shape. There won't be much of a price difference between new and 95% of new.
I've been there and wish I had some of the guns I have sold.

 

[David Berkowitz]

David, is that your real name?

Yup, sure is, only I had it first. I feel sorry for that other fella, having to live with the reputation I started.

You sound reasonable/informed/and well balanced. This is, of course, if it is truly you giving this advice, and not your dog.

Those who know me would probably disagree. But it was me offering the advice. My dog quit talking to me years ago. Stupid to think a dog could really talk.
Now, the cat, on the other hand...