I have to admit that I dont' think i've come across a site....quite like this one. I was looking for movies about psycho kids, and somehow, through the powers of google I managed to find This Site (http://www.blackhorrormovies.com/index.htm)
It's... good. The reviews are a little biased, but it's a good site. Too bad there aren't small bios and pictures for each of the actors they list. That would make it a little more comprehensive.