If I'm in Algoma (this region of Ontario) I say "I'm fifteen minutes up the Chapleau Highway, a little place called Wharncliffe." If I'm in Southern Ontario, I say "I'm an hour east of Sault Ste Marie". That one usually works in the States, too, as Sault, Michigan and Sault, Ontario are side-by-side, but I'll add "Sault, Canada" in case my Canadian accent isn't showing that day.
If I'm feeling bloody-minded, I'll say: "You got a map of Ontario? Okay, look at the top of it. Okay, now turn it over; I'm on the other side."
I always say "Northern Ontario". I believe we should separate from the Greater Toronto Area.