Equipment's easy -- it sits in a Rubbermaid cabinet and if I want to see what I've got, I open the front door.
Negatives: 35mm and 120 are in negative sleeves, in binders, sitting on a shelf. Earler negatives to the left, later to the right. When the shelf fills up I'll find another one. 4x5 are in sleeves in drawers in an old oak library card catalog box I bought at an estate auction. beautiful piece and I'll never shoot enough 4x5 negatives to fill it up. The 5x7 negatives I have left are in one of the drawers, too. 8x10 are in 8x10 page protectors from the office supply place, then stuck into binders like 35mm. I don't have a tracking system: every couple of years I go through a stack I haven't see lately and throw out the obviously really, really awful ones. I always find something or two which I want to print or reprint, and going through them occasionally reminds me of what I have and (approximately) where it's at.