I'm going to Prague in April, been to Budapest once, and am currently living in Vienna. Minus hostels, it seems everything here is pretty expensive, restaurants and hotels especially. After I had been here for a few months, my parents gave me a guide they had when they came to visit. "Rough Guide to Austria" is the name, and it has plenty of stuff that would have been helpful to know earlier :D
So I recommend you get a few of these (or other) guides. It has listings of hotels and about how much they cost, and of course, you can find rooms online as well. The best ones in my experience have been the rather small hotels with only a few rooms run by a small number of people. Not as fancy as the really expensive ones, but my brothers and I stayed in Berlin, Hotel Columbus, it was near to Bahnhof Zoo, we had a nice room 3 people for 100 Euros a night. The owner was quite nice and could do the English. Also includes a decent breakfast, so I think you should check it out at least. By a strange chance I have a picture of the address and phone number so:
Hotel - Pension - Columbus
Meinekestr.5
D - 10719 Berlin
Tel/Fax +49-(0)30-881 50 61
You'll probably want these Pension hotels, since they tend to be cheaper. Not hostel cheap, but you also don't sleep with strange people so much.
As for Prague, I have heard good things, but have not been there yet. Hot babes in Eastern Europe, sucks for you.
For Vienna, just look in a guide and try to find something near the Subway (U-Bahn). It's got some pretty neat stuff. I'll look in that book real quick. If you're outside late at night, check out one of the Würstelstands (sausage stand!) which is basically the only thing open after midnight. If you just want a basic sandwich, Billa and Spar, the two most popular food places will combine some meat and bread for you at a nominal cost. There's the
Statsoper, Schönbrunn Palace, Stephansplatz (with church), the Arsenal (war history museum, maybe my favorite) that I can think of off hand, and lots of random other things, but really a guide would be good for that stuff, since I don't know what you're looking for.
Besides that, if you know a bit of German, it usually doesn't hurt to try and use it when you can, I think the people like it more when you try to speak their language.
So unless someone knows some secret travel trips, I'd recommend you check out some handy travel guides for more accurate and complete information.
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