I have multiple iPhoto libraries w/ duplicates in several. How can I consolidate and find the dupes? Some photos are versions of the original.
To merge libraries use iPhoto Library Manager - http://www.fatcatsoftware.com/iplm/ - or Aperature
To find duplicates within an iPhoto library use iPhoto Library Manager - http://www.fatcatsoftware.com/iplm/ -
Photos that are not in an iPhoto library can be imported telling iPhoto not to import duplicates (an imperfect procews) and then IPLM can find the duplicates
As to keeping seperate libraries - only you can do that - IPLM can move photos between libraries for you but only you can know which photos should be in which library