The major index of popular magazines for this time period. Not fulltext.
Use the advanced search feature of Google books to retrieve Magazine articles, including Life Magazine. Click on the Magazine button. Note: you cannot print from Google books.
Both Lexis-Nexis and ProQuest have newspapers going back to the early 1980s. However for earlier newspapers use:
New York Times Historical Newspaper 1851-last 3 years (moving wall)
America's Historical Newspapers1829-1922
-- Now including over 100 Pennsylvania papers going back to 1719.-- Includes the Philadelphia Inquirer from 1834-1922 (some issues are missing)
In addition, the Library of Congress is beginning a newspaper project: