Andrew Gibbs’ The Dieline is a great website dedicated to designs for packaging. You can view exceptional examples of product packaging design, as well as submit your own for consideration.
They have articles about packaging design, “before and after” makeover stories, competitions, and more.
Helpfully, they also categorize the designs according to Industry and Substrate, so if you’re designing for a particular kind of product, or for a particular material, you can see some interesting designs for inspiration.
Jay Nelson is the editorial director of PlanetQuark.com, and the editor and publisher of Design Tools Monthly. He’s also the author of the QuarkXPress 8 and QuarkXPress 7 training titles at Lynda.com, as well as the training videos Quark includes in the box with QuarkXPress 7 . In addition, Jay writes regularly for Macworld and Photoshop User magazines and speaks at industry events.