Can you tell me if Swedish-speakers outside the Swedish-speaking regions are entitled to use their language when dealing with public libraries?

In principal the answer is ’yes’. According to the new Language Act that came into force on 1 January 2004 state authorities and municipal authorities are obliged by law always to serve in both Finnish and Swedish.

In the following some extracts from description of the law by the Ministry of Justice, Finland:

“Everyone shall have the right to use Finnish or Swedish at their own option in their contacts with authorities. … This, however, does not mean that all employees must master both languages. In practice the authorities can act in the way they consider most appropriate with regard to their own duties. If, for instance, there are several service points, different service points can provide service in different languages. Another possibility is to organize work shifts and work distribution in such a way that employees who master both languages are always available.”

The description in whole can be found in the following address: http://www.om.fi/Etusivu/Perussaannoksia/Kielilaki?lang=en .

On the same site there is a link to the Language Act in its complete form (pdf-file).