First, a tiny map of how the starting line works:
The runners come from the high school via Grove st or Hayden Rowe, or they come directly from a bus by walking down Main st.
Most of the spectators stand at the town common, but this year security was much tighter, so you had to get there pretty early for them to let you on that side of the road. Obviously, once the runners begin to line up, they don't let you cross. I wasn't that early, so I was on the other side.
I managed to get a few pictures. Of the helicopter flyover:
Looking down Hayden Rowe st:
Looking east on Main st, towards the starting line and the common:
Then I took a few panoramas. When they start the waves, the runners are usually walking for a bit because it's so congested.
Then towards the end of the waves, they thin out: