Ryanair and Aer Lingus fly to Salzburg.
The taxi drivers in Salzburg are well used to picking up people at the airport and dropping them to their resort. The cost per direction for us was about €100 (not on the meter) to St Johann, so it would be similar for resorts in that general region. I think the drive was 90 minutes or thereabouts.
We were going to get the taxi to Salzburg train station and get the train from there to St Johann and then get another taxi to our hotel, but it was going to cost almost as much as the taxi door to door and take hours longer so it was well worth it to just sit back and enjoy.
When our taxi driver asked where we were getting the train to and tried to say he would drive us there we were wary of being ripped off, but then we did the sums on the train tickets, the times, etc . . . He also arranged to pick us up for our return flight the next week. All in all, it made life incredibly simple. Turns out he drove Mary Robinson around the area a few years ago and he was full of (nice) stories. . . originally we thought the Mary Robinson thing was a wind up, but it turned out to be true from the detail he gave us. Nice guy.
z