Tigerdirect.ca stuff comes from Canada. I just ordered some components from them, and they shipped from Canada. The laptop I'm typing on right now came from Tigerdirect, though it was a pickup from the Markham location.
If you do plan on buying anything from in-store though, do yourself a favor and call first. They have no online stock checking feature because-- well, I dunno, becuase they're using the 1996 Internet? Often what's on the website isn't in store.
That being said, if you've done your homework and the computer you want is a good one, go ahead and order. Your warranty will be fine.