SSE doesn't have free versions exept trails,
Supposedly the game is so well protected its not on pirate bay - but being censored here I don't know so you have to buy the game to play it
I have already bought all the three versions of ShipSim, SS06, SS08 and SSE 2010 Collector's edition.
What I mean with free Ship Simulator versions, are games manufactured by other gaming compagnies.