Guess I'm still a bit gunshy from the admonishment I got from the 'Big Kahuna' himself eons ago. (That would be JimRob himself to all the newbs)
Nam Vet
The best approach is to hit the abuse button and briefly relay your suspicions to the moderators, who can monitor the situation and have access to IP logs. They do a great job of sorting things out.
We old timers have seen so many trolls, that we know almost immediately, who is a for real troll and who is just some rather lost newbie.
If in doubt, call in the Viking Kitties and RKBA.