There was a comprehensive book simply titled "The PCC Car", IIRC. Try looking for that title on Amazon or Abe's Books. BTW, they are not really pre or post war. The cars were built by St. Louis Car and Pullman to slightly different designs, and some of the cars without standee windows ("pre-war") were actually built after World War II.
Also, you might Google "Presidents Conference Committee" car, which is what "PCC" stands for.