Delray Beach is grooving to the tunes of the ’60s once again as “Beatles on the Beach” festival brings Beatlemania back to the city, starting today at Old School Square. Heads up, music fans: this is your chance to see the iconic Cheap Trick performing live on Friday night. They’re not the only ones taking the stage; tribute band lovers can catch acts from Finland and The Fab Faux-an ensemble celebrated for their appearances on “Late Show with David Letterman” and “Late Night with Conan O’Brien.”