There's an Indian reservation 40minutes NE of Las Vegas...
...with pretty much any fireworks you have the bucks for. I've managed to make a pilgrimage about every other year to create some really spectacular 4th shows for family and friends. Love the mortars!!!
However, most spots in California (particularly in July) are completely inappropriate for most fireworks. I only used mine in Santa Maria which is close to the ocean an has lots of humidity at night.