I googled "bar etiquette" and found, among several B- efforts, this gem. It may not be the best teacher, but it's hilarious.
http://www.facebook.com/topic.php?uid=2232605408&…

Really, like all etiquette, it's very simple: Understand that you're surrounded by other people. (I don't mean to imply that you don't understand this, I'm sure you're a lovely person who does.) In the case of a bar, those other people are many other customers, and one bartender. The one bartender is responsible for keeping all those customers happy. So for their sake, and his, have a general idea what you are doing when you ask for his attention. You don't need to be an expert; you only need to be conscious of that general situation.

Typically this means you should have your money ready and your order ready. If you don't know what you want, you should have one fairly simple question, and a willingness to go with the answer. "What's a good cocktail with bourbon?" or "Do you have any amber beers?" is fine, as long as you're prepared to roll with the answer you get.

If the bar isn't busy, then obviously the situation is more relaxed. This "don't talk to the bartender" stuff is alien to me, because I work at a neighborhood hangout bar where my MAIN job is talking to everyone, knowing their story, and being engaging and upbeat. Except for when I have a line six people deep — but in that case any normal person can tell that the situation has changed, and the rules of engagement ought to also.

In any case, respecting other people, and having enough empathy to figure out how to show that respect, is the heart and soul of etiquette. (And of being a good person, really.) If you can do that, then people will appreciate you regardless of whatever beginner's mistake you might make.

I’ve compiled a list of my own that includes some of the stupidest requests I’ve gotten from people trying to be “classy.” One of my favorites is : Can I get an Extra Dirty, Extra Strong, Belvedere Martini. Still makes me laugh.