I know that comming from Canada to the US, you have to pay an import tax. I bought a set of injectors, and paid the shipping cost to the seller, then got a seperate bill from UPS for import tax. I couldn't believe it, so i didn't pay it right away, they got severly pissed at me and threatened to cancel my ups account. That was the second item i had bought from Canada, it didn't happen on the first order.
Zip.