MaureenB

IMHO, it's a waste of precious vacation time to have to go to the train depot in any city in order to get tickets in advance. Why navigate your way to the station, stand in line and figure it out while your vacation day is ticking away? It can dictate activities of an entire afternoon.
So, I've used budgeteuropetravel.com, 800-441-9413 or 800-441-2387, because they are friendly and helpful and I got all our tickets in the mail before leaving home. They charge one small shipping & handling fee for the entire purchase-- about $15--which was well worth it for the peace of mind knowing I bought the best train fare for us.
And I agree the Prague train station is a bit intimidating. I thought it was an abandoned building when our taxi driver pulled up to leave us there! And, it's not especially easy to find help there, especially English-speaking.