"First, let's no longer answer their posts!"
That's probably a good place to start. All boards will have a troll here or there. It's to be expected. But if you don't feed them, some go post-crazy and make a bunch of threads or get vulgar.
I was just over at the Astros board and Jake / Halo / Justin called me out by name in one of his thread titles. Apparently the dozens of threads he made had been reported, because a few minutes later they were all gone.