Here's a youtube video of Los Lobos at Boarding House Park in Lowell, September 1, 2006.
Some friends and I were in the audience at this show, a few rows back. The camera work is shaky, and there are a lot of people walking back and forth in the pathway across BHP during the song, but the audio is tasty! No, I didn't film this.
http://www.youtube.com/watch?v=vXYOACUMnuc&feature=related