Google's Book Search is now listing magazines. Many full view magazines. Page by page (and of course including ads). There's alot of past issues, maybe 10% which are within this year. Magazines include Baseball Digest, CIO, Women's Health, Popular Science, Indianapolis, Popular Mechanics, Vegetarian Times, Men's Health, and much more.
Few strategies, you can go to
Google Book Search Main Page and keep clicking on the refresh button, to quickly view a few sets of magazines at a time OR
Click on the
Google Book Advance Book Search, select 'Magazines' and do a search.