Spirit may have lost its lawsuit against Led Zeppelin band for the song, Stairway to Heaven, but both classic rock groups have created musical legacies, one with Jimi Hendrix (Randy California of Spirit) and the other as one of the best-selling recording groups of all time (Led Zeppelin has sold over 300 million albums). You’ll not see Zep on tour these days and Randy California has passed away, but there are plenty of classic musicians performing this weekend at California music festivals. Here are a few highlights for the week of June 24-26, 2016…