Best Buy Co. has rolled out a massive makeover of its California stores. The firm converted 68 locations in Los Angeles, San Francisco and San Diego that catered to one or two of five different demographics. Two dozen of the stores will target small-business customers aiming to grow their enterprises, 16 will go after affluent professionals looking for top-of-the-line technology, 16 are for family men seeking technology to “improve their lives,” 12 for suburban moms and 11 are geared toward younger consumers looking for the newest gadget.