One of his best known works is a 1922 novel set in Zenith which concerns a titular real estate agent.  
His "caustic tales about American life" including The Willow Walk are collected in the posthumous collection Go East, Young Man.  After using the pseudonym Tom Graham and publishing Hike and the Aeroplane, this author wrote a man who needed the warm nod of a ticket taker at a Nickelodeon in Our Mr. Wrenn.  A better known novel sees Fran caught up in a vastly different lifestyle than her husband Samuel Dodsworth and another tells of Carol Milford and the town of Gopher Prairie.  One of his best known works is a 1922 novel set in Zenith which concerns a titular real estate agent.  For 10 points, identify this American Nobel Laureate, author of Main Street and Babbit.
His "caustic tales about American life" including The Willow Walk are collected in the posthumous collection Go East, Young Man.  
Sinclair Lewis