I have a couple of small bins with rubber feet next to and beind my seat and next to my wife seat. They stay in place and you can slide them out easy for access.
I also used double sided sticky tape to hold a wooden magazine rack (From Target - around $12 - brown color - looks nice) on the floor but against the wall on the drivers side.
I also put two little mesh pockets on each side of cockpit (below side windows. They hold the cell phones and other nick nacks. See picture below.