Google Magazines includes full-text digitized copies of some historical periodicals. It's a little hit or miss as to what's included, but it's worth checking out... just in case.
Because these are full-text digitizations, searches include the full text of articles and advertisements, so a search in Google's collections may turn up more than a search using a database. (This is definitely the case with Life magazine).
(Be sure to click the "Search all issues" box!)
These are examples of full-text runs of historical periodicals included in Google.