You have to watch shipping anything from Canada to the U.S. or vice versa. All the major couriers/carriers will charge brokerage fees on shipments over a certain value and the fees can be high. The best bet is USPS / Canada Post for most as they do not charge brokerage fees.
If you live in Canada and live close to a border crossing, have your stuff shipped (make sure the seller includes and invoice for customs) to the UPS store in the closest American town or city. Just go and pick it up and "broker" it yourself. (free) You can also bring goods to the U.S. to ship by UPS or USPS. U.S. customs will charge you a "user" fee of $10.75. for the goods you are "leaving" in the U.S. If you do this a lot you can elect to pay a $200. annual fee for unlimited shipments.
Hope this helps!
125" Spitzer Bantam
7.68 @ 176.4