The 20th-anniversary concert from Tinley Park, Ill., includes performances by Willie Nelson, John Mellencamp, Neil Young, Dave Matthews, Kenny Chesney, Wilco, Emmylou Harris, Buddy Guy, Widespread Panic, Arlo Guthrie, Los Lonely Boys, Susan Tedeschi, James McMurtry, Kathleen Edwards and Jimmy Sturr. Taped Sept. 18, 2005.