By airplane there is a fast connection from London Stansted to Graz via Ryanair. Other possibilities include flying to Vienna (2h by car or train to Graz ), Klagenfurt (1,5h by car to Graz) or Bratislava (2,5h by car to Graz). Check the airlines listed below for flight connection details.
from England: Ryan Air www.ryanair.com (London Stansted <> Graz)
from Germany: Air Berlin: www.airberlin.com (Berlin <> Graz)
from Germany: Lufthansa: www.lufthansa.com (via Frankfurt/Main or Munich)
Austrian Airlines: www.aua.com (via Vienna)
Welcome Air: www.welcomeair.at