Is it possible to get a bus/coach direct from Prague airport to Spindleruv Mlyn? And if so, how much would it cost?
Just noticed you asked about buses. None direct from airport. There is an early morning skibus from Černý Most at 6.40 which returns late afternoon. There are buses during the day to Vrchlabi from where you could take a local bus or taxi to Špindl.
BTW if you want some street cred, never say Špindlerův Mlýn. Czechs only ever call it Špindl pronounced Shpindl.