Gotta go with my favorites-
Wreck of the Yarmouth Castle- G Lightfoot- His earlier and imho better shipwreck song.
Dogtown- Harry Chapin- Storytelling at its finest.
Flora- Peter Paul and Mary- Remake of an OLD folk song.
I Will Get My Ship in Order- Ossian
Hard ones but I did find Leaving on a jet plane- peter, paul and mary http://www.youtube.com/watch?v=Fa3h3pnhg8s