Get a commercial account with Amsoil! It costs nothing and you can buy at dealer cost! That's what I have and it reduces the prices quite a bit. They ship from warehouses located all over the US, and I'd bet they have warehouses in Canada as well. The warehouse I get mine from is about 45 minutes away and just up the road from my walker dealer actually. I just order when I'm planning a trip there for something.
Their site is fine to deal with, I've ordered from them half a dozen times at least. Always pay through the website, whether I pick it up or have it shipped. I use Amsoil in all my mowers and trucks. It DOES make a difference. I don't do their crazy long oil change intervals though. I know they say it's not necessary to change the oil more often than even 10,000 miles, but I just won't do it. I'd rather have piece of mind that I have fresh oil.