easiest way - cab (45-60?)
a little harder - air porter (will drop off multiple locations, take you a little longer to get to Cal, so you'll have to coordinate you flight)
hardest (but soooo doable!) take airbart! it's a a bus to the oakland (coliseum) BART station ($2.00 to the Bart station and then ~3 buck to downtown Berkeley) it's how us locals do it!