Organizing a small closet-sized pantry with shelves that have a large amount of space between them is nearly impossible to do without adding additional shelving. This is what my kitchen pantry looked like before I knew what to do with it. It was organized as far as "like with like" and a home for everything, but look at all that unused vertical space!
There were actually a few things I couldn't stand about my pantry...
*TIP: Measure your shelving and the distance between each shelf. If yours are like mine, the distance between each shelf may not be the same, so make sure you draw it out on paper with your measurements before shopping.