Yes, there is a significant IT department, however getting their involvement isn't easy. And they're way overburdened right now, so this would never get done. I've been waiting a year for them to work on a bigger project, not asking for this right now :) Although, ironically I'm doing this in prep for what they're working on.
This is critical data. I can de-dup and reorganize, but can't delete anything completely. In fact, I've already deleted 150 gb of duplicate data, but the pieces I'm working on right now are not that easy. Add in the fact that I have nothing else to do right now (project based, in between projects, and new projects won't start until Jan), so manual checking is not a problem.
jplee3 - I'll check out CloneSpy, thanks. Sounds like that might help. The other dup finders I tried weren't working for what I need, this sounds different.