Catalina Divers Supply at Green Pleasure Pier, Avalon, California.

We made reservations for a boat dive and even had called day before but wasn't notified that the boat was cancelled since not enough ppl signed up.
We went on a shore dive instead and had to pay more for it. But our dive guide Jeff was great. We picked his brain on many things on scuba and he gladly answered our questions. We were a bit rushed at the end of our 2nd dive since they had students coming in and they had fitted us in since the boat dive was cancelled.