everyone has pretty much covered all my fav places in san fran.... but if you want recommendations for Santa Barbara I can give you some as i used to live there...
as Livia said State Street is really cool... Paseo Nuevo (a cool yet somewhat uppity outdoor mall) is located on state street... they have one of the first nordstrom's built in socal i believe (being originally from seattle, it was a big deal to my family when it opened) there are also lots of fun shops on the lower side of state street towards the beach... silver jewelry, vintage clothing shops, head shops, record shops, juice bars... that kind of thing.
you should also go to the pier in SB... there's a really awesome restaurant called Longboards on the pier... inside is ok, but you will REALLY want to eat out on the deck upstairs. they play a lot of beach boys music too.
also... as a stevie/fm fan... you HAVE to visit American Pie records on Milpas. Milpas is an exit off the 101 on the southern side of SB (just a little down from state street) and it's not the best area (well, as far as Santa Barbara goes
) but if you go all the way up Milpas almost to the Santa Barbara Bowl there is this record shop on the right hand side run by this CRAZY old vietnam vet who calls himself Dr. D and likes to talk about his awful exwives. The store is not organized very well but you can say "hey i'm looking for Fleetwood Mac's Fireflies extended mix 12 inch single" or something totally random and rare and he'll go "ok lets look over here" and in less than three minutes he'll pull it out of a box on the bottom of a pile of crap. he always has at least a half a dozen Buckingham Nicks albums... a couple of GYOW/Silver Springs 45s etc... He's a big Harry Chapin fan also... so be careful about getting him talking about it lol i made the mistake of telling him that Harry is my extended family and he had me standing there for 30 mins while he talked about a card he got from Sandy, Harry's widow.
hope you have fun!!! if you have any Q's let me know!