The two telephone companies currently offering service are GSM Åland and Sonera.
Country code: +358 18
White Pages directory for the Åland Islands (an autonomous part of Finland). In the box entitled Sök efter type in what you're looking for. You can refine the search by geographical area and also by business (företag), people (privatperson) or both. Click on Sök on the right hand side of the box to search. In Swedish. Also offers reverse search (by number) - just enter the number directly into the search box and click Sök.
Basic White Pages for Åland Islands for businesses and people. The business search works for free - the search box is on the left - Hae yrityksiä. In order to search people or reverse numbers (Hae henkilöitä in the right hand box) it requires a registration including an SMS to get activated. Registration is currently 30 cents (0.30 Euro) and searches free after that.