One of the things that will probably help is if you indicate what aspect of a 'vocal program' you're most interested in: choral, classical, musical theater, music education, etc. Two CA schools I've seen mentioned here a number of times are UCI and CSLB, albeit for very different reasons. Two lesser posted schools are UCSB and SDSU. I also understand (from other sources) that CSUSacramento has a pretty good performance program that is leans toward musical theater somewhat. I'm sure there are others that will be more helpful to you than I, particularly if you can clarify your intentions or current leanings. Best of luck
Edit: there are a number of strong private institutions, but I kept my response to UC/CSU as your original post specified.