Not directly associated with CA, but I have had some luck finding member requests posted at trap/skeet ranges or in their newsletters. Also newsletters of local chapters for conservation/hunting groups. Knocking on doors looking for properties to hunt - when they say 'leased out', ask about joining [or at least ask for a manager contact]. Might have to check references and scrutinize them a bit more than word of mouth recommendations but it might be an option.
Another possibility, talk to others standing in line at the local WMA - an amazing number of them also shoot leases.