I think there are sufficient similarities between the U.S. and Canada in that you don't have, for example, the language issues that you have with Brazil or Colombia.
To the best of my knowledge, we never sought the assistance of the Canadian embassy in the U.S. We will, from time to time, primarily on immigration and visa issues, write to them to see if they can help, but typically we have not dealt with the Canadian embassy in the U.S.