I must say I can't blame anyone for complaining about US or Canadian postal charges.
A friend sent me a card from Canada the other week and it cost her $3.75 to mail - it wasn't overly big or bulky and I felt really bad that she'd had to pay so much for postage. Total Rip-Off!!
I'm sure it would be worth checking out Momwolf's thread - plus the International rate Flat Pack boxes don't seem to be too over the top, either.
We thought we had it bad over here when Royal Mail started charging for the depth of packages, as well as weight - each time I go to the post office with a package, Bev or Sue, the post ladies, put it through a slot in a plastic 'post box' to measure the depth and charge the appropriate price.
Even with all that palaver, prices here seem much more reasonable - there would be ructions if it cost £3.75 to post an Airmail greetings card of the same size - and I think Hallmark cards would be out of business overnight.
Hope you can find some sort of reasonable postal rate.
Give me a shout if I can help in any way at all.