A long, long time ago there was fery few coin price guides and the Red and Blue books were the way to go. Red for highest prices and blue for lowest prices. Then after a period of time both books became outdated as modernation of communications improved where you could find out the price of anything via the internet. Prices on coins change regularly and the
Red Book comes out to infrequently to be used for valuations. The latest Edition is the worst such case. The 2007, 60th Edition came out back in March or April of 2006 so by now the prices are outlandishly a joke. Utilizing
Red Book prices when attending a coin show, for instance, could actually get a few laughs nowadays.
There are a multitude of web sites with coin prices and as already noted most dealers use the grey sheet. At most coin shows I attend they pass out a magazine of coin prices called "Coin Prices". It's free so I pick one up at each show and I go to about 3 coin shows a Month so I get them all the time. It is advertised on their web site as
https://www.coinpricesmagazine.net Then there is places like the PCGS web site where they have a list of well overpriced coins.
Prior to going to coin shows I print out the PCGS coins price list, go to dealer web sites like Millersmint and print out their prices, put those sheets in the latest copy of that mag I mentioned and go to a coin show. So far I've never ended up using any of that stuff though because at coin shows prices are what they are regardless of any such documents.
But back to the
Red Book. It is just about the most usless coin pricing document available.