I flew into Vienna in September 2012 in an SR22.
At the time I needed to book an arrival slot but this was done relatively painlessly online.
As has been posted before, the airport taxy diagram looks a bit of a nightmare but is not as bad as it seems. I landed on runway 11 having done the ILS, and that positions you nicely for the taxyway to the general aviation terminal.
My departure was off runway 16 which requires a longer taxy, but a close study of the airport diagram before starting made it a lot easier than it initially looks.
Landing fees and three days parking was 216 Euros. The people were friendly and helpful and, whilst the service is unarguably expensive, it is very good.
As posted earlier, taxis are available at the FBO door and there is also a cash machine on the way out.
I hope this helps