Well we just had to do it. It was interesting finding out little bits of odd knowledge about the town but kind of dissapointing IMO. Just walked around pointing out things I mostly found out about on the History channel already.
Unique Suggestions: Get some comfortable shoes and prepare to do a bit of walking.
I suggest going on the earlier tours because the locals were not as disruptive as we saw in some of the later groups as they passed by. Prepare to be heckled by the locals at least a bit while on the tour. It could range from stupid inane comments as they pass by to them actually sneaking in the back of the Hugenot graveyard to "scare" the people on the tour.
Fun Alternatives: Get one of the many books about local ghosts and go around trying to find the places by yourself. The Historic district seemed fairly safe even late at night so a midnight private tour isn't out of the question. There are several maps handed out for free with many points of interest on them, some of them even have the more popular "haunted places". After looking through the books and a map or two I want to try this the next time i go.