I plan to take a morning train from Taiyuan to Pingyao.

Do you mean you only want the railway station pick up and drop off service?
If so, I'm afraid no, as the service is currently only provided in some big cities like Beijing, Shanghai, Xian, Guangzhou, Guilin and Chengdu.
Ping Yao actually is not very big. Upon arrival at the station, you can easily hire a taxi to your destination. For reference, the fare from the station to the ancient town is about CNY30.
Have fun~