Help with train from Vienna to Krakow

I'm trying to get from Vienna to Krakow on the train but I'm having difficult time finding information on how to achieve my goal. My questions are:

1. I know there is an overnight train but don't know how to buy a ticket or how much it costs.
2. Is there a website I can order my ticket from? I've gone on http://www.oebb.at/en/index.jsp but it switches back to German when you click on any of the links.
3. I've looked at Skyeurope and they have VERY reasonable fares but they don't have any tickets available on the 15th.

Thanks in advance for any help I can get :)