Austria is an easy country to drive in, with good motorways (although the Salzburg to Vienna and the Vienna to Munich autobahns tend to be unpleasantly busy). Sign-posting in towns can be poor, and last time I was in Vienna (admittedly about 15 years ago) signs were virtually non-existent. Can anyone tell us if it's better now? You need a windscreen sticker (vignette) to drive on autobahns and expressways, and these can be bought at the frontier and from nearby garages.
Click for more information on driving in Austria.