Although Topanga Canyon has a vibe, it's off the beaten path and it's not conducive to face-to-face interaction...especially when it rains. If traffic jams up, it's a long drive to anywhere.
On the west side, Santa Monica, Marina Del Rey and Culver City were the best locations for me, give the balance of location vs. lifestyle vs. proximity to the music business "action." Of the three, Culver City has the least vibe, but is the most affordable, and you're no more than 20 minutes away from any of the studios and record companies.
Silverlake is hip, and is regarded as a place where musicians (as opposed to producers, engineers, et al.) tend to live. Be prepared to have your car stolen.
San Fernando Valley is a hotbed of activity. Lots of folks & studios... much more affordable, but more smog.... If you land there, try to stay near 101 & 405 Freeway intersection, i.e. Sherman Oaks, for traffic considerations. Access to dining and entertainment is super easy. People in the music business are accustomed to working & meeting there, so you'd be in or near the action.
A recent trend among producers has been to move west of SFV, to places like Agoura Hills, Thousand Oaks or Simi Valley. Simi is farther away from the scene in terms of mileage, but it is typically a faster drive via 118 Freeway. It's 30 minutes to Burbank & Sherman Oaks, or 45-ish to Hollywood & Santa Monica. (101 Freeway can easily add 20 minutes to the drive time--or more than an hour if there's a traffic accident.) Simi has the added benefit of being surrounded by a green belt, and if you're physically fit, you can ride your bicycle to the beach. It's great for people who enjoy the outdoors, and the air quality is very good.
Depending on what you do in the music biz, you could be virtually anywhere, working remotely. There is, however, no substitute for face-to-face networking. Any of the locations above have pros & cons, but they are a good starting place. Good luck with your search!