Tromsö-Norway- where to go to see Aurora - without booking a tour

Hi to all

Will be in Tromsö between 6th and 12th February 2013 and know that the city lights are too bright for Aurora sightings. Also know that there are tours run by different operators that take you to different locations outside of the city. I find these tours a bit too expensive and wonder if any of you know...you might be a local...of places one can go with public transport between 10pm and 1am and that are far enough from the city centre to be deemed 'dark'. Also, how safe/dangerous do you think this endeavour could end up being?? I know this is Norway but still......Any tips and advice are welcomed!!
And many thanks, as always!