Well, there's Pomona, yes...but there's a couple others, also:
L.A. county Raceway in Palmdale and a drag racing facility at Fontana Speedway.
There's total irony in the dragstrip at Fontana, too. That area used to be home of the Kaiser Steel mill and complex. The surrounding areas had wrecking yards with tons of awesome stuff and we used to street race on Saturday nights in that area (illegal as hell and the law used to come down on us like a sack of bricks if we were caught).
A far cry from the strips that used to exist: Orange County International, Irwindale, Lions, Carlsbad, Riverside, Ontario, Ramona, San Fernando (often called the "Pond" and used as a location in many dragracing movies) and San Gabriel.
I was fortunate enough to be a spectator as a kid at some of these legendary tracks and later on, I had the good fortune to run at the ones that still existed. (L.A., OCIR, Carlsbad, etc.)