I swiped a discarded cardboard display with cubby holes from work use that to store the majority of my fabrics. I've only been stashing for about six months so I don't have a lot to organize, but they're either sorted by color or what project they're intended for. Right now I have blacks and whites, blues, purples, Kittie shirts (Kittie is the name of a band I love---see avatar), and superhero logo shirts. There was a few more piles, but I'm currently cutting out those fabrics.