We did it DIY. Booked an apartment through booking.com, flights with Norwegian, with spends came in at £2.5k for 4 nights. Stayed in Rovaniemi, booked excursions direct and hired a car. Would do it again in a heart beat.
We went last Christmas. 2 adults 2 children via Santaslapland.com Kids were 8 and 10. Absolutely amazing and definitely worth it. We were there over Christmas and saw Santa on Christmas Eve!
I think it cost about £4,500 and we booked it in the July/August before we went so it might not be too late for you for this year?
We did it in 2012 via Thomson (TUI now) - 3 nights £2.2k staying from 23rd to 26th December including direct flights, Santa Sport hotel incl breakfast (had swimming pool, spa and children's indoor playcentre), transfers, snowgear and all excursions. Excursions included snowmobile, husky rides, reindeer rides and 3 course lunch, gala dinner with fireworks and Santa appearing arriving by reindeer, visit to Santa, elf workshop, gingerbread making, entering arctic circle, more reindeer and husky rides. Really magical and kids still talk about it. Booked in November to get lower price but think prices have risen quite a bit since.
