That one and
www.allofmp3.com supposedly work because of the way Russian law works.. it is legal in Russia for the moment.
Does that mean those sites are legal here? That would boil down to the importing laws. In the US it is illegal to import music unless it is one copy for personal use. So in the US it is legal to buy from those sites because you are importing a legal product.
I'm not sure about Canada however. After quite a bit of searching I can't find anything about any specific restrictions on importing copyrighted material into Canada.
There's a few articles about this:
http://www.guardian.co.uk/online/story/0,3...1171203,00.html
And their faq:
http://www.museekster.com/allofmp3faq.htm#...llofmp3%20legal?