You have to take taxi from airport, cost 1800 yen. It's really worth if your group is more than 2 persons. No shuttle bus for sure. How ever this is the good price when you are group tour.
Walking from chitose train station is 20-30 minutes, not easy during snow season.
The staff is polite. very impressive. You can tell them to book the designed taxi you need.
Free breakfast with lovely staffs. Great!