1st sunday of every month is onroad racing at Speedtech R/C by OC Circuit.
4th sunday of every month is onroad racing at the Corona Hobbytown USA store by OC Circuit as well.
Traction at both places is GRREAATT!! Especially speedtech.
they also have racing in La Mirada at their Civic Center/Community Center every 2nd sunday of the month and every 3rd sunday of the month at Ultimate Hobbies in Orange, Ca. The people are great and the racing is fun.
Also in Orange is Bending Corners which has a well prep'd outdoor asphalt track and an indoor carpet track. Races every saturday.
and finally theres also Beltran Wheels and Hobbies in Huntington Park.
Beltran Wheels and Hobbies
Street: 2934 East Florence Avenue
Huntington Park, ca 90255-5826
Phone: (323) 589-5100
No official website but they have an rctech thread:
beltran raceway on road in door track