I'm not entirely accent-deaf. While I may notice the odd difference, I can't really tell you where someone is from (region-wise that is, although I can usually get the country right).
I've lived so many different place I don't really have an accent, although I say certain words in ways that I have picked up here and there.
Canadians do have an accent, even compared to Americans, but it's very subtle, you have to know what you are listening for.