Honestly, what we do is just separate them by brand (WD, Seagate, HGST, etc.) and put them into numbered bins which each hold around 10 drives. Then we keep an excel sheet with full specs of each drive listed and the bin number listed. So when I need a drive, I just look it up in my Excel sheet, go to that numbered bin, and I only have to look through 10 drives to find it.
I know some other companies like to separate drives by family and whatnot, but it honestly only takes 30 seconds to find the right drive in a bin of 10 drives.