Need help organizing a big pantry?

I just bought a house with a panty that is basically an open closet. The bottom shelf is about two feet off the ground, runs back 24" to a step that is 24" high. The second shelf is 33" deep. The upper step will probably be used for Christmas decorations or something like that since it obviously isn't easily reached. The problem is the front part. 24" deep 36" wide and goes to the ceiling. I was thinking of bookshelves maybe. This is where all of my food will be kept. I would appreciate ideas that are both inexpensive and maybe more high-end for when I have the money. Thanks!