A Fairfax resident began work this week in her new role as executive director of the West Marin Fund, a community foundation that provides grants for local nonprofits and works to expand social services. Elizabeth Warner, 53, brings more than 25 years of experience in nonprofit leadership to a role previously held by Sarah Hobson. In a June 5 newsletter from the fund, Ms. Warner wrote, “West Marin is an incredibly special place, and I’m…