Anyone know what the procedure is on buying a car from Canada and licensing it here is the US? Thanks

Check with your state's DMV, year of car may dictate some rules (emissions, safety, etc.) I'd bet that different states have different rules for registering a car purchased from another state, or country in this case.

I am talking about a classic car if that helps. Something older than 1975.

I bought my car from Canada. As long as you have a bill of sale there shouldn't be a problem getting the car registered. I did have to pay a $200 customs fee to have it brought across the border.
James

In addition to checking with your State DMV, make sure you check with your U.S. Customs to confirm their requirements. In addition to all the normal customs requirements, they may need to have the title in their hands for a couple of days to confirm liens, non-stolen, etc. before allowing the car to cross the border. What you don't need is to show up at the border with the car and find out you need to leave it there for a couple of days before clearance. Do your homework and you should be fine.

I bought my 69 in Canada and brought it to Michigan five years ago, I had the previous owner get a letter from GM of Canada that documented that the car met all US safety and emmision requirements for model year 1969. I didn't have to pay any duty fees but I was required to claim how much I paid for the car. The Customs people warned me not to lie about the amount because if they found out later I didn't claim the correct amount they would have the right to confiscate the car.

Whatever you do, don't just drive across like you were on a day trip and not go back. One of the guys here did that and like to never got it straightened out. AzDOT was ready to confiscate the car, but seems like it was scarce there for a couple months while the red tape blizzard died down. Whatta mess it was.