Lake Elsinore isn't what I would call LA...
Assuming you need to rent a plane too. You should be checking out schools at French Valley (flyefi.com), Corona (flycorona.com), or Chino (Dubois Aviation). Choosing a flight instructor is a personal decision. You have to have good chemistry with the instructor. A good instructor for one student may not be the best fit for another, due to different teaching/learning styles. It is best to check out a few places and talk to them to see where the best fit will be.
You're going to need to fly at least twice a week, 3 is even better, to make your training efficient. Unless you love spending hours on the freeway, I would only be looking at training within about a 30 minute commute.