Go and check out transportation section from our website
http://www.wasacross.com/index.php?id=15
We are doing our best that it would be easy as possible for you to come here. We have negotiated a deal with SAS/Blue1 and they will give you a discount. I would say that it's cheaper to fly via Stockholm and almost everybody wants to use connection from Stockholm rather than Helsinki. At least most of work mates thinks so...
Remember our shuttle service so it's not necessary to rent a car. Renting a car might be a bit expensive here in Finland