Global Market Information Database - for packaging trends and for what is currently happening in packaging your product. Search using the upper left hand corner search box. Remember to narrow search by "USA" via left side of page. "Category Briefing" reports have trend, competitor, and sales figures and forecasts for your product.
Books - for the history of the product - links to CalPoly's library to search for both physical and ebooks
Articles about Packaging - use for trend information, consumer behavior and desires, and changes in packaging your product
Packaging World - search this for packaging news, trends, and innovations http://www.packworld.com/
Packaging Digest - click on the upper left 'sections' for a list of articles http://www.packagingdigest.com/#menu