Well, TNG: Ghost Ship and TOS: Ghostwalker spring to mind. In addition to Bloodthirst, Dillard's previous novel Demons is pretty creepy. There was also a TNG sequel to Demons called Possession.
There's also the Invasion! tetralogy, featuring the Furies, aliens who are the basis for the monsters and demons of our mythology and who inspire deep-seated fear.
John Vornholt's TNG novel Masks (nothing to do with the episode of the same name) is a natural, though emphasizing a different aspect of Halloween. And Gulliver's Fugitives might work in a similar vein; its antagonists are reminiscent of the religious types who think that dressing up and indulging the imagination on Halloween is satanic and should be banned.