Most of the work I do is residential, and I buy most of my material at either the orange or blue "Big Box" stores. Prices are better than the supply houses, and the stores are everywhere, so I can usually stop by one on the way to the job. For wire, breakers, panels, boxes, etc. they can't be beat....
A real electrical supply house is needed when things get a little unusual, and I need something out of the ordinary, like anything for 3 phase, or a replacement motor or something. Even then, I can often do better at a place like W. W. Grainger than an electrical supply house.
