Letter from Kei 5 is a file in Fatal Frame III: The Tormented.
I got a tape on "The Manor of Sleep" urban legend from a source at the hospital. A psychiatrist had recorded the medical condition of a patient.
There is a lot of background noise as it was originally recorded on a gramophone, but the content is great. It's not quite anthropology, but I think you'll be interested too.
It's a lot to ask, but I'd like you to find out about legends or cases of missing people similar to this one.