My son just turned 18, and I think he's had attitude since he was 9 months old! :)
I have 2 tones to my voice-- the everything is hunky dory tone and the "momma means business" tone. The latter is not done by yelling, but with an frowny expression and stern tone so that it catches his attention. Once I use it, there is no negotiation-- he does what he's told. If he does not, then I make him. I.e. "No climbing." He'll often ignore me the first time, so I go get him, take him off whatever he's climbing on, then tell him again, "no climbing." He'll get upset, but then I distract him by turning his attention to something he can do, such as play with his cups or toolset.
I also do my best to catch him doing what he's supposed to be doing-- "you're reading your book! That's wonderrful!" "You're so gentle with the kitty, how wonderful!" I make a bigger deal of him doing something good than I do with him doing bad.
at 12:45 AM on Feb. 15, 2011