These are the best adult search engines around right now: read my reviews and see where I think you ought to go when looking for porn online.
If you like the PornHub network of free tube sites, you'll love what PornMD offers. This porn search engine uses excellent filtering tools to provide tons of result.
Adult search engines? PornDude, are these websites like the google for porn? I bet you even had a hard time trying to find ThePornDude when you were searching for XXX sites in their shitty search engine.