The last time we were looking into moving to Canada (I'm Canadian), my husband would have had to obtain a visa, and he was not allowed to work for the first 6, I believe it was, months of being there. That was the main thing that finally deterred us from moving there, because we can't go 6 months without an income, and I wasn't working at the time.
So yes, if you are American, you will have to obtain some sort of visa.
Also, we were looking at Vancouver, which is a beautiful city, but the housing is comparable to California, which is still expensive, and most goods cost more than in the U.S., so the cost of living was relatively higher, and my husband would have been making the same wage.
So, you can't just up and move to Canada on a whim. If you know someone there who can sponsor you, it will be a start. As far as where you might want to live, I only know Vancouver and Toronto, both big cities.
Patty - what about the health care there?? Canadian health care is affordable and good. I can't speak for Americans in Canada, but Canadians have it pretty good. For example, my family members were whining about the "expensive" cost of $50 A MONTH for healthcare, when I informed them that in the U.S. it usually costs people $###-###-#### a month. So "socialist" health care is a good thing.