I am a West Coaster.
Asphalt
Irwindale, Kern county, Madera Speedway, Stockton 99 Speedway, All American Speedway in Roseville.
Irwindale is the nicest, but Kern is great too. Madera more than likely has the best week to week count and show and they have a 5k and 10k race annually, but Stockton has years and years of history and is a great bullring. AAS is coming along. Bill McAnally obtained the track last years and he is making the rules comparable to Madera so that they can attract the same car count.
Dirt
Perris, Keller(Hanford), Plaza Park(Hanford), Tulare Thunderbowl, Merced Speedway, Stockton Dirt Track, Placerville Speedway, Petaluma Speedway, Ocean Speedway(Watsonville), Marysville Raceway Park, Silver dollar Speedway (Chico), Calistoga
I attend Merced quite a bit. The just had their promoter pass last year in the middle of the season after taking over 2 years ago and revitalizing the track. A couple of the invested racers there have taken control and have widened and added 12 degrees of banking. Should be even better racing there.
Tulare is a spectacle. Just an amazing place to watch modifieds and sprints. Home of the annual Trophy Cup.
Stockton is just ok, but they get good series and good car count.
Placerville is where I go to see the WoO every year. An amazing little town and a great facility with awesome racing.
Petaluma is fun because it is in the Bay Area and it holds moisture very well. Very racey track.
Ocean is a fantastic place. Great temps being by the water and the scenery is incredible. It is located at the Santa Cruz County fairgrounds and hosts some of the best races every year.
Marysville and Silver Dollar are run by the same person. I have never been to SDS, but it has a great reputation.
Calistoga is the most historic dirt track in CA. Known for it's years upon years of hard top racing and sprints. I believe the Abreu's recently took over 2 years ago and have started to bring it back to life. They host the WoO every year in September. Also a half miler.