Pro-tip: if you're in Canada and you receive any letter or email alleging that you may have violated someone's copyright, THROW IT STRAIGHT INTO THE SHREDDER.
It is a 100% guaranteed empty threat that they are powerless to do anything about. They do not have your contact information. They have only sent the notice to your ISP, whose only obligation is to forward it to you and not not share your contact information.
Legislation has deliberately made it unaffordable for copyright holders to sue alleged infringers to prevent the type of extortionate fiascos that have happened in the US.
As scary as they may try to make the letters sound, they are 100% certified bullshit.