Fiction:
* The Psychic Sleuth series:
* The Psychic Sleuth: The Ghost of the 19th Hole
* The Psychic Sleuth: The Ghost of the Old Courthouse
* The Psychic Sleuth: The Ghost of the Abandoned Mill
* The Psychic Sleuth: The Ghost of the Haunted Hotel
* The Psychic Sleuth: The Ghost of the Old Mansion
* The Psychic Sleuth: The Ghost of the Haunted Schoolhouse
* The Psychic Sleuth: The Ghost of the Old Cemetery
* The Psychic Sleuth: The Ghost of the Haunted Theater
* The Psychic Sleuth: The Ghost of the Old Lighthouse
* The Psychic Sleuth: The Ghost of the Old Train Depot
* The Psychic Sleuth: The Ghost of the Abandoned Church
* The Psychic Sleuth: The Ghost of the Old Inn
* The Psychic Sleuth: The Ghost of the Old Post Office
* The Psychic Sleuth: The Ghost of the Haunted Museum
* The Psychic Sleuth: The Ghost of the Abandoned Barn
* The Psychic Sleuth: The Ghost of the Old Jail
* The Psychic Sleuth: The Ghost of the Haunted Mine
* The Psychic Sleuth: The Ghost of the Old Bridge
* The Psychic Sleuth: The Ghost of the Old Shipwreck
* The Psychic Sleuth: The Ghost of the Old Fort
* The Psychic Sleuth: The Ghost of the Old Plantation
* The Psychic Sleuth: The Ghost of the Old Saloon
* The Psychic Sleuth: The Ghost of the Old Graveyard
* The Psychic Sleuth: The Ghost of the Old Library
* The Psychic Sleuth: The Ghost of the Old Theater
* The Psychic Sleuth: The Ghost of the Old Hospital
* The Psychic Sleuth: The Ghost of the Old School
* The Psychic Sleuth: The Ghost of the Old Church
* The Psychic Sleuth: The Ghost of the Old Lighthouse
* The Psychic Sleuth: The Ghost of the Old Mill
* The Psychic Sleuth: The Ghost of the Old Mine
* The Psychic Sleuth: The Ghost of the Old Castle
* The Psychic Sleuth: The Ghost of the Old Ship
* The Psychic Sleuth: The Ghost of the Old Train
* The Psychic Sleuth: The Ghost of the Old Airplane
* The Psychic Sleuth: The Ghost of the Old Rocket
* The Psychic Sleuth: The Ghost of the Old Time Machine
* The Psychic Sleuth: The Ghost of the Old Ghost Town
* The Psychic Sleuth: The Ghost of the Old World
* The Ghost Hunter series:
* The Ghost Hunter: The Haunting of the Old Mansion
* The Ghost Hunter: The Haunting of the Old Asylum
* The Ghost Hunter: The Haunting of the Old Cemetery
* The Ghost Hunter: The Haunting of the Old Lighthouse
* The Ghost Hunter: The Haunting of the Old Mine
* The Ghost Hunter: The Haunting of the Old School
* The Ghost Hunter: The Haunting of the Old Church
* The Ghost Hunter: The Haunting of the Old Hotel
* The Ghost Hunter: The Haunting of the Old Theater
* The Ghost Hunter: The Haunting of the Old Prison
* The Ghost Hunter: The Haunting of the Old Ship
* The Ghost Hunter: The Haunting of the Old Train
* The Ghost Hunter: The Haunting of the Old Airplane
* The Ghost Hunter: The Haunting of the Old Rocket
* The Ghost Hunter: The Haunting of the Old Time Machine
* The Ghost Hunter: The Haunting of the Old Ghost Town
* The Ghost Hunter: The Haunting of the Old World
* The Paranormal Investigator series:
* The Paranormal Investigator: The Case of the Haunted House
* The Paranormal Investigator: The Case of the Ghostly Child
* The Paranormal Investigator: The Case of the Demonic Possession
* The Paranormal Investigator: The Case of the Haunted Asylum
* The Paranormal Investigator: The Case of the Haunted Cemetery
* The Paranormal Investigator: The Case of the Haunted Hospital
* The Paranormal Investigator: The Case of the Haunted Theater
* The Paranormal Investigator: The Case of the Haunted School
* The Paranormal Investigator: The Case of the Haunted Church
* The Paranormal Investigator: The Case of the Haunted Hotel
* The Paranormal Investigator: The Case of the Haunted Prison
* The Paranormal Investigator: The Case of the Haunted Ship
* The Paranormal Investigator: The Case of the Haunted Train
* The Paranormal Investigator: The Case of the Haunted Airplane
* The Paranormal Investigator: The Case of the Haunted Rocket
* The Paranormal Investigator: The Case of the Haunted Time Machine
* The Paranormal Investigator: The Case of the Haunted Ghost Town
* The Paranormal Investigator: The Case of the Haunted World
Non-fiction:
* The Encyclopedia of Ghosts and Spirits: A comprehensive guide to the world of ghosts and spirits.
* The Complete Ghost Hunter's Guide: A practical guide to investigating paranormal activity.
* The Paranormal Investigator's Handbook: A guide to conducting paranormal investigations.
* Ghost Hunting: A Beginner's Guide: A basic introduction to ghost hunting.
* Ghosts: The Real Story: A look at the history of ghost hunting and the science behind it.
* The Case for Ghosts: An argument for the existence of ghosts.
* Haunted Places: A guide to the most haunted places in the world.
* Ghosts: Real or Imaginary? A discussion of the evidence for and against the existence of ghosts.
* The Afterlife: What Happens When We Die? A look at the different beliefs about the afterlife.
* The Psychic World: A guide to the world of psychics and mediums.
This is not an exhaustive list, but it provides a good overview of Loyd Auerbach's published works.