If you live in the United States, then diedinhouse.com is the site you'll want to visit for this information.
They provide an interesting service for homeowners and homebuyers who want to make sure they don't have a ghostly spectre, unpleasant memories, or a haunting vibe on their hands.
They don't really approach the whole matter from the "paranormal" angle, but rather the financial fallout of being associated with a death in the property is what drives their business.
