In Reply to: Re: Re: Visiting SoCal in October posted by James Padfield on July 22, 2010 at 09:13:45:

The Magician runs Friday trips to Catalina out of San Pedro (Port of Los Angeles). I sometimes go on these trips. The Peace in Ventura runs a Thursday trip, but during October they have multiple day lobster trips.
The Sundiver Express runs 2-dive trips out of Alimitos Bay.

You can look on the dive boat page and call some of smaller boats and see if they have trips. However midweek trips in California are the exception rather than the rule. The slow economy has reduced the available pool of divers and the number of trips available has decreased correspondingly.

Whoever you book a trip with I would confirm it about a week before since most boats do not run unless they have enough passengers to break even. Your chance of finding a mid-week oil rig trip is extremely low.