Billy began playing piano at the age of 5, violin at the age of 7, ukulele at the age of 10 and guitar at the age of 12. He formed a successful pop music group in the mid-sixties with friends Dino Martin, Jr. and Desi Arnaz, Jr. known as Dino, Desi & Billy (DD&B). Their audition for Reprise’s Frank Sinatra lead to 4 successful albums, 6 songs on the Billboard & Cash Box singles charts and appearances on every local and national television show of the era including Shindig, Shivaree, Hullabaloo, Where The Action, 9th Street West, The Mike Douglas Show, The Joey Bishop Show, Sammy Davis, Jr.’s Wonderful World of Children and The Ed Sullivan Show in1965. DD&B appeared as themselves in the film Murderer’s Row starring Dean Martin (as Matt Helm), Ann-Margret and Carl Malden, and they did a television commercial for Royal Crown Cola that can still be seen on YouTube.
The young trio toured extensively as the opening act for The Beach Boys, Paul Revere & The Raiders, Sam the Sham & The Pharaohs and headlined their own tours throughout the U.S. and Canada.
He recorded and toured with The Beach Boys as a vocalist and member of the band during the ‘70s, ‘80s, and ‘90s and has performed in every major venue in the world including The Hollywood Bowl, Madison Square Garden, Carnegie Hall, and Wembley Stadium in England. He has played for 4 U.S. Presidents.
Billy toured with the Carl Wilson Band in the early ‘80s and the Brian Wilson Band in 2007.
Billy has enjoyed success as a songwriter and his compositions have been recorded not only by Dino, Desi & Billy but also by Dean Martin, Nelson Riddle and Beach Boy Carl Wilson, Billy’s brother-in-law. His songwriting credits include the theme song “Automan” (1984) for the Glen Larson produced television series of the same name, as well as a songwriting credit on the I Love Lucy 50thAnniversary Television Special of 2002 for “Patria” featuring multi-Grammy Award winner Arturo Sandoval on accompanying trumpet. He co-wrote “Lady Love” with Brian Wilson, “Away” with Dennis Wilson” and “Let’s Build a World” with Carl Wilson. He recently co-wrote “(Because) It’s Christmastime” with Rock & Roll Hall of Fame/Songwriter Hall of Fame inductee Robert Lamm, who is a founding member of the group Chicago. The song is the first song on the first side of the new Chicago Christmas album on Rhino Records. The album recently debuted at #1 on the 2019 Billboard Holiday chart.
His credits include singing background vocals on the original recordings of Elton John's "Don't Let The Sun Go Down On Me," The Beach Boys’ “Heroes & Villains,” Warren Zevon's "Desperados Under The Eaves" (produced by Jackson Browne), America's "Hat Trick," Joan Jett's "Good Music" and many more.
In 2006 he hosted Rickenbacker International Guitar’s 75th Anniversary at L.A.’s House of Blues:
He has been a counselor at the Rock ‘n’ Roll Fantasy Camp several times featuring guest appearances and performances by Brian Wilson, Jeff Beck and Paul Stanley of KISS.