Pick up local tours as you arrive, or just wander round. Book hotels on something like hotelopia - or just google 'hotels in vienna' etc and pick them from the map
Spend the money you save on having a brilliant time!
Apologies to the Cleckheaton Chamber of Commerce - Don't sue, I'm sure that any native of Prague would have a mind expanding experience in your fair city....
If you go to Vienna, take with you a copy of
Setting Free The Bears by John Irving.
Start it before you go.
Any tour of Vienna will take you to the Schoenbroen Palace (not sure if that's the right spelling), and the squares in the town close to the Sacher Hotel (also not sure of spelling), and you will be swept away like never before.
Venator - why on earth would you roll up in a place with no accommodation arranged in advance?
This internet thing..... hotels use it too......
I believe you get much more out of a trip that you plan and control yourself, rather than sitting on a tour bus as a 'freelance gawper' being told daft lies and taken into 'my cousin's shop'.