Use the databases ProQuest or Academic Search Complete to search for magazine and newspaper articles. Remember to limit to only magazine and/or newspaper articles by checking the appropriate boxes by source or document type or by narrowing to source type after you search (see images below).
As shown in the image below, the advanced search page in the databases allows you to control the results you see.
(click on image to enlarge)
Limiting in academic search is very similar to limiting in Proquest. You can limit to a specific source type while you're on the first, advanced search page, or you can wait until you enter a search and see results, then, use the limiters on the side.
(click on image to enlarge)
For more search tips and information about popular sources like this, consider the guide linked below:

Image: Evan Sung for Bloomberg Businessweek. "Living in the United States of Food Waste." Bloomberg Business. Jan 10, 2013. Retrieved from Bloomberg.com.

Fig. 4. Alland, Alexander (Photographer). "Street Scenes - Newsstands." Collection: Photographic views of New York City, 1870's-1970's. NYPL Digital Gallery. 1938. Web. 2/4/14
When you search the library's periodical databases, most articles in your results are either from a newspaper, magazine, or journal.
You are required to find a magazine or newspaper article as a source for your Background Essay. Why?