Open Library
Horror
Fear is the oldest story.

Sweetwater Night
Alison Stewart
The Complete Tales & Poems of Edgar Allan Poe [67 stories, 50 poems, 5 essays]
Edgar Allan Poe

Once Upon a Zombie
Storm Stoker

Scary Stories
Barry Moser

Dogwitch
Daniel Schaffer

Poison Pages (Library of Doom)
Michael Dahl

The Smashing Scroll (Library of Doom)
Michael Dahl

Gezellen van de dood
Catherine Duval

Ravens Deep
Jane Jordan

House of Fear
Jonathan Oliver

Rubberhead
Steve Johnson (1960-)

Staplegun logic
K. K.

Charla
Alexander Beresford

The Haunted Mansion Mystery
Virginia Masterman-Smith

The Murders in the Rue Morgue and Other Tales (Fall of the House of Usher / Gold Bug / Murders in the Rue Morgue / Mystery of Marie Roget / Purloined Letter)
Edgar Allan Poe

Demonic, Dangerous & Deadly
Helen Hoke

The Norton Anthology of Short Fiction -- Shorter Seventh Edition
Richard Bausch

Lords of Salem
Rob Zombie

Short Stories, Please!
Hilary Laurie

30 Tales to Give You Goosebumps
Robert Lawrence Stine