Warren Fitzgerald is the guitarist for The Vandals. He has also played with Tenacious D and was a member of Oingo Boingo, performing on their final studio album and live album. One of Warren's first bands was Dies Irae where he played bass with guitarist Jack Galbraith-Taylor and drummer Robert A. Smith. Later he formed the band Totally Uncalled Four and was in a hardcore punk outfit called Don't No. He was also the guitarist and songwriter for Xtra Large. Fitzgerald also produced Jughead's Revenge's 1996 album Image Is Everything. He was also playing guitar with The Offspring on their 2008 tour.
Apart from performing as a live instrumentalist, Fitzgerald has also worked as a composer and songwriter, having worked with a wide range of musicians including Dweezil Zappa and Danny Elfman, and has written songs for the movie School of Rock. He also provided string arrangements for the Alkaline Trio album Crimson and contributed guitar work to the Team America: World Police soundtrack. As of 2012, Fitzgerald is credited as a writer and composer on The Hub cable series The Aquabats! Super Show!, including a co-composing credit for the series' theme song and several onscreen appearances playing a hobo.
Outside of his music, Fitzgerald finds work as both an artist and a writer.