I'm just basically looking for hints & clues . . .
Well, when you find some let us know.
Seriously, though, the scheme of 9/11 evolved over time, like I said, in the same way that the idea to assassinate JFK evolved in certain circles of power over time.
As far as finding the actual players who did 9/11, who wrote the script and carried it out, until you're willing to give your life obtaining the necessary security clearances, you'll never know who they were.
But they can easily find out who you are . . .
Understand the underlying infrastructure of secrecy,
and you will find the hints and clues you're looking for, if you make a lifelong commitment.