My grandfather was from Canada... I don't know if that makes me part Canadian (it's not really an ethnicity, is it?).
Canadian bands/artists I've heard of in the U.S.:
Triumph - I always liked Triumph, despite being a "poor man's Rush"
Max Webster - The only reason I've heard of them is due to their connection with Rush. I used to have a bootleg of "Battle Scar" featuring the two bands playing together.
FM - Again, awareness through association with Rush.
Boys Brigade - Only heard of them because Geddy Lee produced one of their albums and mentioned them in an interview once.
Men Without Hats - I thought for sure they were from the U.K.
April Wine - If you were alive during the '80s, you've listened to April Wine... admit it!
Helix - Didn't know they were Canadian. Never listened to them, but I've heard of them.
Loverboy - Didn't know they were Canadian either. Almost as disposable as Honeymoon Suite, though (IMO, of course).
Honeymoon Suite - Saw them live during their 15 minutes of fame back in the '80s (opening for Jethro Tull... whaa??)
Our Lady Peace - Not a fan... just heard of them.
Tragically Hip - Same as OLP
Glass Tiger - Ditto
Bruce Cockburn - I'm SURE I've heard his stuff, but nothing springs to mind.
Kim Mitchell - Same as above.
Five Man Electrical Band - Another OHW I didn't know was from Canada.
Barenaked Ladies - I wouldn't say that they're obscure in America as someone suggested, though. They were pretty well known in the states for a while.
Jacob Moon - Got turned on to him through his acoustic Rush and Marillion covers. Never heard of him before that.
Corey Hart - Got nothing to say about him.
Bryan Adams - Equally ambivalent.
I'm sure there are others, besides the obvious Joni Mitchell, Neil Young, Anne Murray, etc... I just can't think of any more right now.