abebooks.com is outrageously expensive

Try Bookfinder.com. As a "meta-search engine," it checks numerous used book sites (including Amazon and ABE Books) for available titles. I don't know if that necessarily solves your particular problem (perhaps you should be writing to your local politicians about the weak Canadian dollar or the outrageous cost of mailing items to Canada), but it does ensure that you are checking the widest range of sites available.

One caveat, though -- Bookfinder isn't perfect, as I've occasionaly found the book (or found it cheaper) on one of the regular sites after Bookfinder turned up nothing. The site is a good place to start, but it isn't infallable by a stretch.

Amazon is much better for regular books. I thought abebooks was specifically for somewhat rare and expensive books? I'd go there if I wanted, like, a specific edition of some obscure avant-garde book of poetry, not so much for regular book buys.

We sell on Abe, and they are based in both Canada and Germany, thanks to bizarre banking laws that make it cheaper to locate a company's hq in one of those places.

Abe's automatically generated shipping rates are usually at least twice the real shipping rate, so I'd check with the bookseller about that, but I don't see how Amazon is going to get your shipping rate down any lower than the actual cost of posting things to your country.

That said, Abe is definitely trying to position itself as a marketplace for hard-to-find books, first editions, old manuscripts and so on, and that's what most people list on there, because it's not cheap to list there (€15 a month for 50 books) so I don't know how people make money from the stack-em-high sell-em-cheap paperbacks.

If you're willing to put up with amateur standards of quality control (ABE is professional) and stick to fairly recent books, half.ebay.com runs cheaper than ABE. But for a $1 book from the US, your problems will be the same. See if you can persuade ABE to filter for country-preference?

try searching for abebooks on amazon.co.uk. they're signed up as one of amazons marketplace sellers. there you'll pay amazons marketplace p+p instead of the ammount abebooks requests (or something like that). see:
http://s1.amazon.co.uk/exec/varzea/ts/user-glance/A3ENSIQ3ZA4FFN/