Right, ok, the original outlines for episodes 7, 8 and 9 (according to Gary Kurtz) basically involved the story NOT being ended in ROTJ (though it would have been left at some closing point; it just wouldn;t have ended with the fall of the Empire).
Luke's sister (who was not Leia) would have turned up in the sequel trilogy, and the Emperor would have been saved until number nine.
All massively irrelevant now.
Slightly roundabout URLs, but never mind...
They should help you.