Andy Samberg\'s publicist says the U.S. actor and writer is engaged to musician and singer-songwriter Joanna Newsom, his girlfriend of five years. People.com confirmed the betrothal Monday, but did not say when or where Samberg and Newsom intend to exchange vows. No details about how Samberg proposed to Newsom were reported. The couple attended Saturday\'s Independent Spirit Awards in Santa Monica, Calif. Samberg served as host of the event.