Hi Crystal Creations,
Sorry to hear about your struggle with figuring out the cost of shipping to Canada.
I am not an expert on customs fees, but from the previous discussions, I remember some jewelry makers mentioning that they usually ship USPS first class international and on the customs form check "merchandise" and enter the purchase price for the value. Since your value amounts are small, there probably won't be any customs fees.
I've also heard an advise from someone not to mark the parcel as a "gift", so that the customer is not charged customs fees on their end. It's not only illegal, but could also cause problems with the Canadian Customs and for your buyer.
As for the taxes, we let PayPal to calculate taxes when the buyer is going through our Checkout process. Please check your setup for taxes in your PayPal account. I don't believe you can charge international customers (incl. Canadians) any taxes, but again, I am not exactly sure on the rules in different countries. All I know is that you do not have to generate a separate bill for the buyer.
Hope our US jewelry makers will chime in and offer your some advise, as they are more knowledgeable on this topic.