2 questions regarding insurance & Oby/Gyn

Cathy
Question: I wasn't prepared to be pregnant. Meaning I have a PPO and heard that when pregnant a HMO is better. Is it that much of a cost benefit? Also, I only was seeing a family practitioner and no Oby/Gyne. Now I need to pick one. How do I choose one without being able to ask friends for advice without giving away my reason why?