Police in Pingyao

Public Security Bureau

Next to the Píngyáo fire station on Yamen Jie, also known as Zhengfu Jie. You cannot extend visas here, but you can in Tàiyuán (although it takes seven working days).
Post in Pingyao

China Post

Handily located at the centre of the old town.
Bank in Pingyao

Industrial & Commercial Bank of China

ATM just west of the old city wall.