You really should visit before you decide to move.
I'm of the opinion that anything down the middle of the state from Lebec north to Stockton is a rathole armpit, and I live just north of Stockton.

Regardless, it's one of the premier agriculture regions of the world, and it's going full bore right now. At least there's one thing that's better than where you're at now, and that's the Mexican food.
You shouldn't have any problem registering your vehicles, so long as there's over 7500 miles on each. But nothing here is cheap, tax/fees wise. Be prepared to bend over. If you're into guns and that sort of stuff, Kern County tends to be a firearms friendly community.
Bankrate does a pretty good job of simplifying the income tax:
California state taxes
BTW, it may be a little higher if the Democrats have their way for the state budget, which by the way, is late again.