Cheonan Train Schedules
There are two types of trains in Korea - the regular train and the high-speed train which is called the KTX.
Luckily, there is one train station (Cheonan Station) and one KTX station (Cheoan-Asan Station) in Cheonan. Cheonan Station is located downtown. Cheonan-Asan Station is located near Buldangdong at the border of Cheonan City and Asan City.
Log onto http://www.korail.go.kr/2005/eng/index.html for the Korean Railways site. You can check train schedules for regular trains and the KTX. The site has an English version.
If you have a Barota membership card (20,000 won refundable deposit) you can reserve tickets on-line. This is a really convenient service.