We would always fish out of Zihautanejo. We would get checked into where ever we are staying and 1st thing head over to the pier in Zihau. Many charters start coming in about mid afternoon. You can watch the flags on the boat and see who is catching what. Will be plenty of guys asking if you want to fish. We did this right away to get booked for a trip in the next day or two.
We would often fish with Pauly on the Don Gordo. Had about 50/50 successful trips to no fish trips. All where fun. His wife has a restaurant right at the end of the pier. As you walked in from the pier this place was directly in front of you.
Barre de Potosi is another place we used to hang out for the day and fish. It is a beach just south of the airport. Have shore fished there and also taken a panga out of their.
Good luck down there.