I pay about $11 Canadian per roll at home which is a lot better than what you're paying. It gets down to about $9 a roll when I buy a pro pack (20 rolls). The US prices are tempting me, however, especially now that the Canadian dollar is worth about 90 cents US.
When you're buying film a roll or two at a time, it won't make sense, but if you can afford to buy 10 or 20 rolls, mail ordering is an option. You might want to wait until autumn, though, so that your film isn't cooking in some delivery truck somewhere.