My approach to a stash is a little different. I "buy" only if it is a great deal I can't pass up or I "find" yardage at garage sales for practically nothing. I also buy (regular prices...) for a specific quilt I'm planning to make. Right now, I have fabric purchased for the next three quilts that are planned for differant people.
Even so, though, (sigh.....) sometimes a fabric will speak to me and I will have to have it. I buy a couple of yards and take it home and enjoy petting it until it has a specific purpose.
I sort by color but honestly the stash really needs some refolding and organizing. I use shoe holders that can be hung in a closet. It isn't working too well as the weight of the fabric is exceeding the capacity of the shoe holders.