You can use the box office just outside zellerbach auditorium on the cal campus (I noticed when walking by the other day) : http://tickets.berkeley.edu/ticket_office/how_to_order.php
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In Person
The Ticket Office is located at the northeast corner of Zellerbach Hall on the UC Berkeley campus. Ticket Office hours are: Mon-Fri, 10 am - 5:30 pm; Sat & Sun, 1 pm - 5 pm, and approximately one hour prior to curtain. (Holiday and University break hours may vary; please call for updates before visiting the Ticket Office.) There are no handling fees for most events when purchasing tickets in person (may vary by event).
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Outernational Music Festival featuring theThievery Corporation and special guests Seu George, Bebel Gilberto, Los Amigos Invisibles and Federico Aubele.