I've read a couple of spooky YA books this month; you might also enjoy them:
1)
The Night Gardener by Jonathon Auxier - this is a story about wishes, and how they can corrupt you if you let them have too much power. Juvenile fiction, but middle-grade vocabulary. I'd say suitable for ages 8-12 (unless your kid is a precocious reader and likes scary stuff.)
2)
Insanity by Susan Vaught - YA title about a haunted insane asylum turned modern mental hospital, and the people with otherworldly abilities (possibly fairy-related ancestry) who are drawn there to keep the ghoulies at bay. Very atmospheric, and a fun, easy read. (Some cursing - 'bitch', for ex,, and references to child murder, so I'd recommend 12 and up as a general rule. YMMV, of course.)
Next I'm going to read "The Doubt Factory" by Paolo Bacigalupi - I love his work, even if it's occasionally difficult reading.