There are only 3 rules to drinking, period.
1. You can drink too much, but you can never drink enough.
2. Drinking doesn't make you more interesting, it makes everyone else more interesting.
Last one is one of Coglin's Laws:
3. I don't care how liberated this world becomes a man will always be judged on how much alcohol he can consume and a women will be impressed whether she likes it or not. (Note: This doesn't mean how drunk you get, rather how much you can consume without being sloppy. And it is a truism)
As far as bar rules, keep in mind people go to bars for 1 of 3 reasons: to get drunk, to get laid, or to fight. All three are perfectly acceptable. So in my day, if you dumped your beer on me and it was one of those nights...I'd knock you out. Not to mean, just for fun. I also got knocked out a few times, but it was always just a good reason to get more drunk!
Have fun out there newbies!