Maybe Weird Tales?  I know some people would argue that they now just do a bunch of "new weird" but still.  I've had a subscription with them for the past year and have not been disappointed.  Cemetery Dance and ChiZine  have a lot of clout, too.  There's lots of markets that publish horror, albeit not exclusively (Clarkesworld, for instance), and often, which you can find for free (including ChiZine).