I really wish I could recommend Canada Post for all your shipping needs. I'm a firm believer in public systems, especially for universal needs such as postal service. Unfortunately, I can't recommend them for most of your needs (but I'm harassing them to wise up!) The biggest problem, as an independent author/publisher, is that they don't have a book rate. Yes, practically every nation in the European Union has a book rate. Even our usually less public service minded friends below the border, the U.S. of A., has a book rate. But, apparently, Canadians don't deserve a book rate. (Unless you're Amazon.ca or Indigo, in which case you get special treatment.) But, if you've got a little novella that's smaller than 380mm x 270mm x 20mm and weighs less than 500 grams it can be mailed as lettermail, which is a good deal. And don't forget, often it makes more sense to send 4 of these little books in 2 envelopes, so that they go as lettermail and are not bumped up to package size. One thing to look into, as an indepedent publisher, is Canada Post's Venture One program, that gives you 5% off of all post purchases. You can also save a few bucks by ordering pre-paid ExpressPost envelopes in bulk.

Unfortunately, if you've got a standard sized book (250 pages or more) it's unlikely to make it as lettermail. Without a book rate, Canada Post has no way of distinguising between mailing a book and an small stereo, so you're shipping will go through the roof. CanPar is a good alternative, running about a buck cheaper than CanadaPost and delivering to Canada and the US. I'm not sure how far it delivers outside of major centres, though, so check that beforehand.