Hello, I'm the Webmaster of a relatively new site for lost and found pets in Canada. It seems to have helped a few people so far (we've had a few e-mails from owners of lost animals who have found them through the site).
The site is CanadaStrays.com
www.canadastrays.com
It's free to use - we are all volunteers who run the site and we care very much about pets, and animals in general.
Gary.