Hi and moi
Bebek is actually in Lahti, they have A LOT of stuff, some really good, some used or salvaged from products or overstock, and very good prices.
They are not that much into Arduino.
The web-address is www.bebek.fi and the shop is at Hirsimetsäntie 26.
Another good source with a good webshop is Partco, www.partco.fi and they are in Helsinki.
They have quite a lot of arduino-stuff, and also otherwise very good service.
Then You should check out www.robomaa.fi, www.probyte.fi, www.vekoy.com
Good luck