Complex sentence: The Alice in the song is Alice Brock, who had been a librarian at Arlo's boarding school in town before opening her restaurant, and who now owns an art studio in Provincetown, Massachusetts.
Split into simpler sentences: The Alice in the song is Alice Brock, who had been a librarian at Arlo's boarding school in the town before opening her restaurant. She now owns an art studio in Provincetown, Massachusetts.