Thanks for the facts, Yvonne. www.vr.fi you can see train timetables from tampere to helsinki. From the airport at Tampere you must take a bus to center. I think I told the timetables at this site to Anna in June, perhaps you'll find it here.
When you arrive at tampere railway station, I would like to recommend a really nice (and cheap!) pub called Ale pub. Anna already tried it and loved it :) There you'll see pure finnish life and typical finnish people :)
I think we will find enough space for us at our flat so you don't have to go to a hostel.
I'm really waiting for my trip to Copenhagen next weekend. It's so rainy and dark and boring here that otherwise I would get depressed.

have ordered a lot of snow already, let's hope that the delivery is here when Yvonne & co. arrive.