Ghost hunters

Here is a free game that has a secret society of mediums and necromancers called the Twilight Order.
These guys tend to act as border security between the living and dead, protecting the living from the dead and preventing the spirits of the dead from being exploited by the living.

If you want a more low powered game, Hunter the Vigil has a compact of bloggers and hackers who hunt down evidence of the paranormal, kinda like a cross between Mulder's hacker friends in the X-files and the amateur ghost hunters in Supernatural.

This this is a link to the Orpheus game I was telling you about it has been described as- if the kid from sixth sense grew up and created a corporation.