Mark,
I wish I knew enough to be of some help here, but I'm afraid I can't be, as I lack experience with Canada into USA transactions. I believe that in addition to US Customs paperwork, that there may also be some EPA issues to contend with (see: http://www.epa.gov/oms/imports/forms-resources.htm).
My advice would be to engage a broker to arrange everything for you. They may be able to help you avoid falling into a hole that is hard to get out of later. Best of luck!
Mark
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