For someone who just went to his first coin show, you sound pretty cynical. Why wouldn't you care what a seller thinks, even about price guides? Perhaps they might have some information or advice that would be helpful to you, especially to newbies. Coin shows are a great place to learn and dealers, who have the time and are willing to help, have a lot of experience and can help guide a new collector. Don't be so quick to ignore what a dealer has to say, you might just want to listen first, then you can use it or discard it.
I must say that I am a bit surprised by this discussion, and the OP's question: why would it not be "OK" to take a price guide to a coin show or store??? Is there a law against it? Here in Europe I take whichever numismatic references I want, and consider useful to a coin show, and will NEVER consider even asking the question. I decide.
taking a Redbook would be silly, like a BB-gun to a tank battle take a current greysheet unless you have memorized hundreds of grades and prices if you forget to bring one just ask the dealer what the greysheet is on a particular coin if you are really interested. real professionals have no problem telling you price guidelines they are using and if their price is higher they will explain why If thats a problem you dont want to deal with them anyway, their are too many decent helpful dealers just around the corner. Even the best dealer may politely put you off for a few moments if he is negociating a $5000 deal and you want to ask about a $25 buffalo. Wait your turn even if you are the 5g and the other guy is the buff buyer. what do you see at your local coin club bourse night? Redbooks? of course not, everyone has a loupe on their neck and a greysheet in their pocket and they are only collectors trading among themselves
What I like to do is get a make a list of coins I want to get before the coin show and put the max prices I would want to pay for the said coin. This way I don't spend to much on a coin I can wait for and get it at a lower price. Of course this only works with some sets but I find it to be the best way for more common sets or coins. I get my price from looking at a lot of other price guides and also taking in the factor of how badly I want that coin. It's always a good thing though to bring along some price reference for the unexpected things that you might find. I hope this helps.
Some Coin Dealers I have dealt with are overpriced and will take advantage of you, If you do not have some guideline to go buy. Going with something is better than nothing, All the money I saw being exchanged at the Houston coin show was shocking. Sure I am cynical about what I said, This guy sounds like a new collector and is just asking if a redbook is ok to take to a coin show and I see NO problem with it. There seems to be some that are too good and proud to be seen with one.