Im from San Diego, and learned to fish in the San Diego area.  You said you would be temecula and sd, if you have a couple of days, try to head up to big bear creek or lake, those are probably the best trout areas around there-about 2 1/2 hours out, otherwise, Doane Pond, on top of Palomar mt will have REALLY good fishing for stocked and hold over trout, thats about an hour or so, and Lake Cuyamaca is a little farther, but much larger, and boat able/tubeable/wadeable.  Everything will pretty much be a stocker, except big bear creek.  One thing is that they have NO rain down there-seems impossible, but they are in the middle of the driest year on record-so creeks might be dry. 

If you dont want to hit trout, bass will be in pre-spawn, dropping clauser minnows and crawdads work.  But the best fly fishing around there will be at the beaches   Surf fishing is awesome-and the surf perch are running at the moment, if you know how to tie sand crab flies, go for it, you can get sand sharks also with those, as well as halibut and corbina.  Best time to hit the beaches in morning (6-11) or evenings, around Torry pines state beach (if you are brave, the best fishing is at a "clothing optional beach , blacks beach, down a big cliff, just south of torrey).  I dont know any good places up north.  If you have a day, and a boat, try the bays down there. Clausers and other streamers that resembe anchovies tend to be the ticket, and you can have 50 or 60 fish days if you fish it right.

Let me know if you want directions to any of these places.  And let me know how the fishing is in my old home waters.

check out the message boards at sdfish.com too if you want.  They have TONS of info, and lots of post from just san diego.  If you want to know what is working and where, they will point you in the right direction, not to mention having decades of advice to offer.