Los Angeles is a great market for conducting focus groups.  L.A. is so large and diverse, there are several alternatives inside and outside the city central that you can recruit any kind of group easily if you want to conduct qualitative research in Southern California.

Moderating focus groups and drawing respondents from the westside of Los Angeles and areas surrounding Hollywood, is great for many subject matters such as household appliances and other durable goods, consumer packaged goods, QSRs and sit-down restaurants, and of course anything affecting the affluent market or for a more diverse target.  Some of the cities to draw from include Santa Monica, West LA, Beverly Hills, Brentwood, Pacific Palisades, Malibu, Mar Vista, Venice, Marina del Rey, West and East Hollywood and Los Feliz.

While focus groups on entertainment are often conducted within the city central, it can be difficult to find untainted or overly-educated respondents in the subject matter, particularly among children and teens.  It's tantamount to finding a group in Washington D.C. that doesn't already have above-average knowledge or associations in politics.  Still, there are places in Southern California where moderating focus groups on entertainment properties can work if you are looking for more of a middle America attitude.

For entertainment research as well as toys, video games, real estate and others depending on the subject matter, consider moderating focus groups in the counties surrounding the city central:  Orange, San Diego, Ventura, San Gabriel and San Bernardino.  If you need to stay closer to the office, your home or the airport, the San Fernando Valley also offers several great options.  

If there is a facility you like in Los Angeles - particularly the recruitment - they often are able to handle the recruitment for you to fill a different market.  Many of the large focus group facilities have field offices in outside counties.  Moderating focus groups in Los Angeles offers a diverse platform to conduct all kinds of research.