I have had reason to order olive trees from Temecula Olive twice now.
Both times, the customer service was great. The questions I asked were answered patiently, the pricing was reasonable, the plants large, and the trees, when I received them were healthy and better than expected.
They grow the trees on their own ranch in San Diego, and are not just a clearing house.
Hopefully I won't kill any of my olive trees, but if I do, I'll certainly be getting my replacements for Temecula.