SBU is easly accessed from Arlanda Airport by the airport coach "Flygbussarna" (http://flygbussarna.se/en), direction Cityterminalen.The bus leaves every 10 minutes, bus stop: "Norra stationsgatan".
If you come by train - get of at Stockholms central (central station) and change to the Metro system. Take the green line (direction Hässelby strand, Åkeshov or Alvik) to Odenplan. Then walk 10 minutes to SBU.
Coordinates: 59° 20' 49" N 18° 2' 25" Ö