Tromso in Northern Norway has a good reputation as a base for seeing the Lights. Both Thon & SAS hotel chains have hotels there. The best viewing point is at the top of the cable car at midnight.

Just remember that the Lights are not guaranteed to be visible on any particular night. You may like to consider doing a round trip on the Hurtigruten (Norwegian Coastal Voyage) from Bergen to Kirkenes & back. It's a 12 day trip & most of the time you're above the Arctic Circle which improves your chances. Plus you can book a phone call with Reception to ring you at night if the Lights appear after you have gone to bed.
Definitely the most civilised way to approach the problem.

Good luck

Dave