Source : Webster's Revised Unabridged Dictionary (1913)

Orderer \Or"der*er\, n.
   1. One who puts in order, arranges, methodizes, or regulates.

   2. One who gives orders.

Source : WordNet®

orderer
     n 1: someone who places an order to buy
     2: an organizer who puts things in order; "Aristotle was a
        great orderer of ideas" [syn: {systematizer}, {systematiser},
         {systemizer}, {systemiser}, {systematist}]