A great place to start looking is Slouppi - Areas -section: http://www.slouppi.net/allAreas.phtml
Vaasa is one of the best places in Finland for Bouldering... There seems to be something around Imatra as well. You should find a lot of info by browsing the Slouppi pages. And there is a topo-book, covering the whole Finland, sold in almost all Finnish climbing stores. You can find the climbing stores and additional info by surfing to:
Maybe you already checked these, in that case, try contacting the local guys in Vaasa or Imatra, or the other places you visit. You should find some contact info at the beforementioned links-section... The Vaasa-local guys can be found at: http://www.highsport.fi/
Hmm... The topos are in finnish. Well, still plenty of time to learn a new language
. Anyway, you'll probably find the locations without being fluent in finnish...