Later this month, the Kennedy Center hosts An American Playlist, three days of free performances to celebrate the Center’s Arts in Crisis initiative. Two free tickets will be distributed on a first-come, first-served basis to each person in line at the Kennedy Center on Saturday, July 10, 2010. At 10 a.m. in the Hall of Nations States, tickets will be available for the July 18 show, featuring The Roots’ ?uestlove and Black Thought. Tickets for…