I think it depends on what you plan to purchase. There should be no discrimination about being from Canada.
However rates can depend if you will live here full time, if it is an investment property, if it is primary residence, your income, debts, ability to pay, reserves, etc. With all that said some lenders don't always know how to verify this type of information or pull credit reports on non-citizens. We assist buyers and sellers from all over the world and have a good group of lenders who are experienced in lending to non-US citizens. Feel free to send me an email and I can forward you their contact info.