good brand of digital-to-analog converter in Canada ?

If you plan to use it right away, be sure to get one that has "analog pass through." That will enable you to see your analog channels that will remain on the air until your digital cutover date, 31 August 2011. The link below shows an example.

Beyond that, any digital-to-analog converter for over-the-air use that's suitable in the U.S. will also work in Canada, as both use the same digital TV standard.