Where to find low bars and whats the angle for?

I ant to get into a more aggressive postion but dont know that i want to go as far as clip ons yet. So i am looking for a really low bar flat with no lift would be perfect. Second i found some drag bars but they are straight across no angle I see all super bikes have a angle what does this purpose do. I also found on another thread from here a ducatti s4r look alike handle bar or something but couldn't find it again in the search feature.