Ideas for Europe
 

Thinking about Amsterdam, Rome, Florence, Split, Dubrovnik, and Santorini- ideas, itineraries, advice, travel plans! anything would be great really. there for a month

A general guidebook on Europe might be of some help.

Look for cheap flights between Amsterdam and Rome: http://www.flylc.com/directall-en.asp#.UuRLnfaIbLs

Take the train to Florence.

A ferry to Split and then another to Dubrovnik might be the travel mode along the Adriatic.

I'd look at Venice, Pula, Trogir, Split, Dubrovnik as a good exploration of the Venetian Empire and it allows you to combo train, bus and ferry with perhaps even a little island hopping.

Six venues in 4 weeks?

Plan 3 trips in advance and plan geographically.
What I see here is a shotgun approach. Just Greece and Croatia could take a month.