I have the 9/11 commission report, which I found at a thrift store for about $3. I've started reading it a few times, but never followed through to finish. Also, on YouTube, you can find the original news broadcasts as the events unfolded live. It's eerie, and I keep wanting the outcome to be different as if I was watching a movie and didn't know the ending, but unfortunately we do know the ending and it's heartbreaking every time.
