When I was a kid I used to tag along with my dad to hardware stores like this. These people know building and hardware and they always have time for your questions. If they don't know the answer, they let you know and refer you to someone who does. Cooper's has a big inventory, but they are more impersonal and Home Depot-like. Don't go there if you want to bounce a building concept off someone. This is the place! Also a great place to get dependable referrals for professional contractors when your wife tells you your do-it-yourself project is out of control.