this is my first trip to Beijing. Travelling alone from shanghai by rail and arriving at Beijing South Railway station (NOT main station) please advise cheapest way to get to hotel at Jin Tong Xi Road, Chao Yang District,(either by Metro or bus?? which station do i get off?

In the event that I take a flight into Beijing, what Express/shuttle bus do i take from airport to get to the same address?

Please advise, thank you