I have heard several conversations among people who believe that they have a haunting. Many times these people just want to know how to get rid of the damn thing. Then inevitably, someone always brings up the whole burning sage thing, or having your house blessed sort of treatment.
I'm not saying these are bad ideas, but I've never really been sold on this sort of lore myself. I found this excerpt from a website for one of the ghost hunter groups out there. I think anyone who believes that they may have a haunting of some type should definitely read this.
"If you conclude that you do have such a situation, realize that you and/or one or more household members are part of the problem. Consciously or unconsciously, people in troubled houses always have a part in causing and/or feeding the phenomena. So you need to find what you're doing that's introducing or encouraging negative energy."
Here's the link http://www.strangehappenings.org/I-Have-Ghosts.htm