I e-mailed Atkins to find out if they had any plans to make their products available at Canadian retailers as I do not wish to purchase food online. This is part of the reply I received today (I still feel there are more products available in the USA that are not mentioned here though ... ):

Thank you for your inquiry.

We're happy to inform you that several of our most popular product lines are now available in Canada in bilingual packaging. You should be able to find the following products in most leading food, drug and natural food stores including A&P, Shoppers Drug Mart, GNC, Savon Foods, Loblaws and Overwaitea Stores:
Atkins Advantage protein bars in Cookies 'n Crème, Chocolate Peanut Butter, Pralines 'n Crème , Chocolate Coconut, Chocolate Mocha Crunch and Almond Brownie.

Atkins Endulge chocolate treats in Caramel Nut Chew and Peanut Butter Cup

Further good news is that Atkins Quick Quisine bake mixes, ready-to-drink shakes, shake mixes, nutritional supplements and more will be available shortly in Canada, so please check our web site www.atkins.ca often for up-to-date information on Atkins products in Canada. You can also purchase many Atkins products and Atkins-approved low carbohydrate foods online at www.atkins.com .