"Piano Man" Billy Joel isn't wallowing over his spilt with estranged wife Katie Lee - the singer stepped out on Monday with a new gal in New York City!

"This is Deborah Dampiere," Joel said as he introduced his date to "Extra." The couple attended opening night of the Metropolitan Opera, dressed to the nines.

"She does some acting and all that stuff - not singing though," Billy says of Dampiere. Deborah chimed in, "A little singing," and said to Joel, "not like you!"

When asked to show off his singing chops, Joel joked, "Do I wanna sing a few bars? You'd have to go to a few bars with me."

Joel and Lee announced their split in June 2009.

"I don't care what you say anymore, this is my life" Billy Joel once sang, and now he plans to put that life story between hard covers.

David Hirshey, senior VP and executive editor at HarperCollins, said Tuesday that the "Piano Man" is working on a memoir, written with veteran entertainment journalist Fred Schruers.

"We paid a healthy advance," said Hirshey, who denied that Joel had received $3 million, as reported Tuesday on Roger Friedman's Showbiz411 blog for the Hollywood Reporter. Joel's agent on the deal is Amanda Urban of ICM.

The book has "been in the works for about a year," according to Hirshey, who said Joel hasn't delivered the manuscript yet. No publication date has been set.