http://pl.ivisa.com/passport-renewals/united-states
As for the Canadian Passport Renewals, it is actually quite cost effective, as opposed to the U.S. Passport Renewals where the processing fees can be exorbitant, depending on which part of the world you reside. Also, if you do not live in Canada, but are interested in getting one, you have no need to worry about the Canadian Passport Renewals being denied.