I've done this myself, but it was from Brissie to Calgary. (I was born in Melbourne, so don't draw too many conclusions, they'd probably all be wrong).
You haven't indicated if you're coming in as a landed immigrant or just on a work Visa.
First thing you need is a SIN number (Social Insurance Number), it functions as a Tax Number.
Second thing you need to know is that until you're available to work, there's very few who will take the time to talk to you.
Third. The Canadian Revenue agency "encourages" arms length relationships with end clients, so there's many recruiting houses prepared to take 25% or more off the top for your services. If you approach the clients directly, you can often find the same work with only a $3-$5 cut.
Forth. Everything which is different is small. You'll handle the big issues like driving on the right simply. It's all the cultural quirks that'll take the time to work out and you'll offend people without even realizing it, and they won't tell you you've done it (Aussie's are used to this service). Luckily your Aussie accent will help get you some slack and most Canadians are pretty friendly.
Oh, yeah... Expect to suffer the loss of many things you didn't realize you would miss... 4n20's timtams (mentioned above), Almost any of the decent dessert snacks you're used to, Decent pavlova, Weet-bix, Vegemite(Now that the Americans have banned it, it's not being shipped to North America)
Finally just expect everything to be different and you'll cope alright. Watch the slang, and any expressions you've picked up from home, sometimes they just don't translate (Cigarettes, and Erasers for two well known examples).
Good luck and enjoy