I love reading Art Journaling from Stampington & Co. It's a quarterly publication. Products I see used a lot throughout the magazine are gesso, markers, and paint. All other materials used seem to be random collections of anything - really! Things like junk mail envelopes, clothing tags, magazine ads, newspaper, tissue paper, etc.
I recommend looking through an issue or two or Art Journaling. The featured artists always have a tips sidebar in their articles plus you can see the ways they use products.