This isn’t actually Halloween related but there is plenty that is spooky or ethereal in the massive trove of images that the British Library has uploaded to it’s Flickr account. Some 1 million of them in fact. There’s a page with various albums, including maps, children’s book illustrations, historical events and so on. And yes comics, mostly broadsheet cartoons. The images have been cataloged and tagged by online volunteers from images that were automatically uploaded.
Sadly many of the artists aren’t known, but that may make these images even more spooky.