I was working construction at the time, on the tools. I'd gone to the shop that morning to pick up some materials, and not really talked to anyone. The shitbox plumbing van I was driving had a broken radio, so I didn't hear anything on the radio. I got to the jobsite and as soon as I got out a couple framers on the roof were listening to a radio that was turned up pretty loud, and there was some talk about a small plane maybe having hit one of the towers. We didn't think much of it and continued working. At morning coffee break, around 9:00am MST (11 EST), we mostly sat and listened to the radio. It's kind of amazing in retrospect how slow news moved back then compared to now. By that point both towers were already down, but as far as I remember, it was unclear if both towers had been hit at that point, if it was just a Cessna that hit, etc. By lunch time, so around 2pm EST, it had become clear that it was jumbo jets, both towers were down, and it was most likely Bin Laden behind it.
I don't really remember much else of that day in specific. We worked a normal day, and I'd imagine I went home and watched news coverage of it the rest of the evening.