I have the shipment sent to a close to the border Fed Ex station to be held there and pick it up in person. That way I take it across the border myself, declare what I paid for the item (you should see the looks of disbelief on the agents' faces, no not because the value is low but they simply can't figure out why a guy should buy a used amp or cd player and pay way way more than a new one at Best Buy), but save the horrendous so called "brokerage" fee charged by the shipping companies. The shipping is cheaper too. I know, I know, this is of no help if you live, say, in Edmonton or Cornerbrook.
No duty on items made in the US, just GST and PST. I got Linn products with a declaration that they are made in Scotland or GB or the EU across and never was charged duty either, just taxes, for reasons that escape me.