how would I go about finding inventory/assemblies that are dead? We have lots and lots of items/assemblies(formulas) that we don't use and haven't used in a long time. I know it would be a saved search but I want to make sure that I can see the last time it was touched/used/transferred and start from the oldest and work my way up

Transaction search grouped by item max of date will give you a list of all your items with the most recent date of a transaction.