How to get to Prague, Czech Republic, from Linz, Austria??

I have a eurailp, entitling me to travel to 18 countries in 15 days, but the countries do not include Czech, I believe in order to go to Prague, I need to pay an additional supplementary fee. Can anybody tell me how much it is? Or maybe suggestan alternative way to get to Prague from Linz, Austria with a cheaper, more affordable fare? Then I need to get from Prague to Nurnberg or Munchen Germany too, maybe by bus? Where do I check online for schedules of different transportations?