If you want bulk prices, that is typically looking at 50 flats or more.
Where are you from, that will narrow down where to start asking. Our club doesn't buy online, but from wholesalers.
As far as reloading, it depends on what kind of a deal you get on components. Same thing as buying bulk shells, if you buy enough components, you can start to save money, the big cost seems to be shot right now. If your in Ontario and close to hummansons you may find it economical to reload, I've started to make my own shot, and that is why I'm considering it.
However if you take the Wholesale sports catalogue, and work out the costs of reloading, the savings will be very minimal compared to buying trap loads in bulk, or even compared to the value packs at walmart.