I'm 90 minutes south in San Diego. I know there are lots of options within 60 miles of San Bernardino. More than I can list here. I haven't personally fished waters in the San Bernadino area so cannot give specifics.

Two sort of local clubs are Deep Creek Fly Fishers based out of Riverside
www.deepcreekflyfishers.org

and Streamborn Fly Fishing Club based out of Rancho Cucamonga (meet at the Bass Pro Shop there!)
streambornffc.org/