My mother went there last summer with my aunt and a couple cousins. They had a wonderful time! They visited relatives near Helsinki and then made their way into Lapland: they visted Rovaneimi (home of Santa and his reindeer!) where there were more relatives, then they visited the area around Ruka-a ski resort area.
They went to spread some the ashes of my cousin who had spent time living in Finland and teaching at a school near Ruka.
She had a hard time adjusting to the constant daylight, it made it hard to sleep. Some of the food took getting used to as well, but overall they had a wonderful time. She wants to go back sometime soon and get my dad to go with them this time.
I believe she used a lot of websites to find attractions, visitfinland.com is one I just googled for names of some of the places they visited.