Where can I get clothes online when I live in Canada and am 6'1"?

I'm finally starting to look more like how I want to, but there is one giant issue, and that's clothing. I have no idea where to get clothes that fit me, being 6'1" and 240lb. And the sites I do manage to find are really expensive and/or based in the USA, which means I need to deal with customs when it crosses the border.

I just want to know if there are any good sites out there for someone in Canada.