Local audiences first came to know Liza Oxnard as the gutsy vocalist for Zuba, a position she enjoyed for more than eight years. But after that group disbanded, the singer, guitarist and songwriter decided to strike out on her own, rather than retreat into the past. So far, she seems to be on target: In 2001, she recorded It's About Time, a joint effort with longtime friend Bill Nershi (of the String Cheese Incident). Later, she formed Liza and the Soulstars, a refined combo that includes keyboardist Eric Deutsch of Fat Mama and Sally Taylor/Sherry Jackson drummer Brian McRae. The band performs Saturday, January 11, at the Fox Theatre and opens for Liquid Soul at the Bluebird Theater on Thursday, January 17. Oxnard puts a feisty and feminine veneer on the high-elevation rock made by her peers in bands like SCI and Leftover Salmon. Live, she can now claim almost any room as her own.