it depends

It depends....

As a general rule, you will need to pay import duty, brokerage fee (for those who will handle the import for you), and 7% GST, but you DO NOT need to pay 8% PST.

But, if the product is 'manufactured' in the US, you may not need to pay import duty according to NAFTA, and thus, you may not need to pay brokerage fee as well.

Personally, I bought quite some books and CDs/DVDs from US (e.g. via Amazon.com, not .ca), I've never pay any tax, not even the 7% GST. Well, I had to pay shipping though since the international orders cannot be qualified for free shipping.

Also, my orders were usually small, usually less than 100 USD. Don't know if this was a factor for don't need to pay duty.