Here's a good article
And more here and here. And here
and there's some cheaper deals here no idea if they are any good.
Am glad you asked this quesiton as I was plannign on doign a bit of research myself later in the year.
Form these reports it sounds as if the Lapland experience is just as touristy as the UK one, so far as the parents are concerned, though the kids in the articles seem to have been won over by the real lapland more.
I think staying overnight would be worth the extra cost (especially as you arrive just as the sun is setting).