Since I recently found a post by someone wondering how to find markets for horror fiction, I figured I’d pass the information I gave him on to you. I don’t submit my work much these days, but these are the links that most of the speculative writing community uses:
http://www.ralan.com/ -While Ralan tends to lean more toward science-fiction than horror, it does contain a fair bit of both. Additionally, it probably updates the most religiously of the three sites I’m going to mention (or at least it did when I used it).
https://duotrope.com/ -Duotrope is a great site for searching for any kind of market, regardless of genre. The site features an excellent search engine that makes it very easy to find a match for your criteria (length, payment, etc.). About the only bad thing about Duotrope is that it now charges users, but you can try it out for free to see if it’s worth the price.
http://thegrinder.diabolicalplots.com/ -The Grinder came to my attention only within the last year or so. The site is essentially a Duotrope clone, but it’s free to use. As it’s new and not as well known, there are less statistics to draw from on the market listings, but it’s still a good tool.