I haven't shipped much out lately, but I usually ship with Canada Post.
One thing worth looking into would be Canada Post's
Solutions for Small Business program. It's free to sign up for and helps to save a few percent on shipping parcels. It isn't a major discount, probably only 5 or 10%, but it's still better than nothing.
Shipping packages internationally from Canada seems to be a great example of how Canadians get price-gouged when compared to our friends down South. From what I've seen, it seems to be much cheaper to ship from the USA to Canada with tracking than it is to ship from Canada to the USA with tracking. However, I'm quite interested in seeing if there are any better deals than the normal Canada Post international shipping rates, so I'll be keeping an eye on this thread.