Greetings From Western Canada!!
First of I would recomended seeing BC and the Alberta rockies as they beautiful. There is nothing else like them. What I would do would be to fly to Victoria and tour the island as it is amazing. Then I would fly to Vancouver (From victoria), rent a car and drive through BC, banff, Canmore, Kananaskis, and Calgary.
At Calgary I would fly to Ottawa and rent another Car. Then I would drive through Quebec to New Brunswick. Spend a couple days there and then drive to Nova scotia. Go to Halifax then drive to Sydney (Nova Scotia). From there I would take a ferry to Newfoundland and tour there for a couple days. Then come back to Sydney and drive to Prince Edward Island tour there for a couple days.
Then I would drive through the States down the East coast through Maine, New York, Virginia, Florida. Tour there for a couple days and then Fly to Denver, Colorado and drive through, Colorado, New Mexico, (Or Utah depending if you like mountains of desert better. Utah has mountains and New Mexico is desert), Arizona, Nevada, California, To San Fransisco. Then I would fly back to Australia.
Here are some websites I would visit:
http://www.travelalberta.com
http://www.travelnewbrunswick.com
http://www.bbcanada.com
Also I would come in the summer as in Canada it gets very cold in the winter!!
Sincerly, Barkley