i'm seeing a lot of you guys quoting from imdb.com which is i think the best online database for movies on the net. but there is a german equivalent called Online-Filmdatenbank which has the great advantage of more or less complete lists for the different versions of a movie (uncut and cut and if so, how much). and as far as i can tell you can find there almost all of the horror movies there are.
sure, the site is in german, but finding the right movie shouldn't be too hard, even if you don't speak the language.
Here's the link
http://www.ofdb.de
So, have fun looking for uncut versions...

or rather :-o