The Letterboxer's Companion by Randy Hall (Mapsurfer) now in its 2nd Edition
It's a Treasure Hunt! Geocaching & Letterboxing by G & R Publishing
Dartmoor Letterboxes by Anne Swinscow
More Dartmoor Letterboxes by Anne Swinscow
101 Dartmoor Letterboxes: But Not How to Find Them! by John Hayward and Anne Swinscow
Dartmoor Burial: A Claire Camden Mystery by Audrey Peterson (letterboxing elements in story)
Chesapeake Crimes III (anthology) (short story about letterboxing "Inked to Death") Shelley Shearer (Knights of Columbo)
Scavenger by David Morrell (letterboxing elements in story)
Let's Go Letterboxing by Janet Palmer (out of print)
Dartmoor Letterboxing by Kevin Weall (out of print)
