All Z autowrecking in Chula Vista Californian. South of San Diego.
From my experience they have been very good and very cheap. I have only bought interior pieces so i dont know about prices on other things.
You might find a Z or 2 in almost any junkyard. But several places specializing in used Z parts advertise or are listed in the Links portion of this website. You can also find them on the Parts & Accessories page of this site. Just tell them what you are looking for.