Julie, this is the paper that I use - Epson Premium Presentation Matte.
The Staples website doesn't seem to show a similar paper in their own brand. But generally, I think most of the hybrid babes use some brand of matte presentation paper. It prints much truer to color than cardstock, uses less ink, and is a nice heavier weight than most photo papers. The paper I use is 45lb weight, which is very close to what Andrea uses, so something in that range would probably be good to look for.