Well I remember when I joined up you couldn't post anywhere else but these forums, and I wanted to ask the same questions on the Canadian forum but couldn't. So it might still be the same way now so I will try to help you.
Canadian customs do not permit the importation of juice, which means that you either have to order from a Canadian supplier or risk having your shipment from the U.S. or China seized. Having said that, most orders pass through customs and this is how the Canadian suppliers and some other Canadian vapers get their stuff. If you are going to go that way, people have better luck with some companies versus others. I actually get my juice from a buddy who has a little business built up and he gets his from Freedom Smoke USA and has had very little trouble importing. I'd order from them myself but it's too easy to email my friend and get him to drop off the stuff to me.
A good place to start is just to do a google search for e-juice canada or something similar. You'll find a few options. A lot of Canadian vendors are a little paranoid so over at the Canadian forum you ask people to PM you with some suppliers. For now though a search will put you in touch with some of them, sometimes you have to create an account before they show you the real juice, so keep that in mind.
Welcome and happy vaping!