How does California Lemon Law apply to interstate purchases?

Let's say you want to buy a used or certified pre-owned car through eBay Motors. You the buyer are a California resident, but the seller is in, let's say Arizona. Which state's lemon laws apply to the purchase? Is the buyer protected under California's lemon laws, or does the state of the seller determine lemon law jurisdiction?

It doesn't.

Both states have lemon laws, although I don't know which state's laws would be used.