Both Alternative and Empire have actual retail locations.
Empire is very involved in the local scene. It's actually my local shop. I try to shop there as much as possible.
Since they don't carry NS, I've had good luck with the Boardroom in Vancouver and Alter Ego in Winnipeg.
No insult to those two, I know that they've got a local presence too, and if I lived around them I'd shop there first. I try to give the guys near me in Toronto a chance, if they don't have it in stock then I go online.