Shipping to Canada starts at $0.67 per ounce for USPS Airmail-Letter Post. This'll cover nearly anything under 4 lbs, and should arrive in 3-5 business days. You can always ship Parcel Post, but IMO that's effing ghetto and in my experience, unreliable.
Anything heavier than 4 lbs. must ship USPS Global Priority Mail, which starts somewhere in the $8 range and includes a tracking number.
Hope that helps you out - you didn't give me much to work with.