Go to Find a Doctor on At Your Service. You will find lists of participating physicians on each insurance plan website.
HMO medical plans require you to select a Primary Care Physician (PCP) to manage your care. When you pick your PCP you are also choosing a medical group (e.g. Mercy Medical Center). HMO physicians are affiliated with a medical group of specialists and hospitals that you may use for non-emergency care. The PCP you select will oversee your care and authorize visits to specialists in the medical group.