I'm trying to find unique weapons placed in the game that comes from fook2, but there's generally no information online where they have been placed so i thought using the G.E.C.K. by cross examening the cell window. Problem is i can only look at one location at a time and there are too many so i was wondering if there was a way to filter what i was looking for through all of them at once. Can that be done?

Yes it can. If you right click on the weapon in the GECK, you'll see a header called "Use Info". Select that and a small menu will pop up showing you where it's being used in the game. You can then double click on the entry in the menu to take you directly to the item.