We recently underwent some big time changes to improve efficiency and reduce errors in our warehouse. The first step was when we decided that to make everything easier, we were going to color coordinate our supplies and inventory.
We purchased storage racks with bins and made sure to order different color bins for each shelving rack. All of our small supplies and parts went into some red bins while our most commonly used supplies went into the yellow bins. This color coordination definitely reduced the amount of errors and the amount of time wasted having to correct those errors. I highly recommend that you think about organizing your warehouse in a similar fashion. We purchased the shelves and bins from Monster Bins.