EBSCO is a collection of ten databases that you can search simultaneously, each with its own strengths and weaknesses. The following EBSCO databases include newspapers and magazines:
Academic Search Complete - Multidisciplinary (Has a little bit of everything)
MasterFILE Elite - popular magazines
When searching EBSCO, don't forget to click on "Full-Text" and "Peer Reviewed."
Canadian Major Dailies contains articles from all of the major English-language Canadian newspapers. Coverage includes the latest issue and, in many cases, goes back to the late 1970s/early 1980s.