I have looked a lot online but I am reaching the end of my search. I was wondering if anyone knows where I can buy miniatures of the Four Horsemen of the Apocalypse — ideally resembling the Pathfinder description, but I will take anything that is close.
Games Workshop has a line of Lord of the Rings miniatures, among which there are nine for mounted Nazgul. Any of them would make servicable horsemen, though I would recommend, "Khamul the Easterling" for the Horseman of War, and, "The Tainted" for the Horseman of Pestilence. They are a bit pricey as the models come in pairs, one mounted and one on foot.
That link should provide you with all of them, but if for some reason it doesn't work you can find them using the categories, "Mordor" and, "Heroes." They do not show up under, "Cavalry."
try this link - these figures looks pretty impressive. http://www.keepwargaming.co.uk/reaper-fantasy-25mm28mm--four-horsemen-of-the-apocalypse-15-p.asp