“Los Angeles Plays Itself” is a movie about movies about Los Angeles. It’s nearly three hours of film clips shot in or about Los Angeles. Nothing’s added except a sardonic, deadpan voice-over. A college professor and filmmaker named Thom Andersen premiered his film at the Toronto Film Festival in 2003. Since then, it hasn’t been widely available outside of the occasional art house screening. Now - at long last - it’s coming out on DVD.