You can buy it at Sapporo Station. Or any other major station in Hokkaido.i will be departing Furano for Asahikawa airport, what transport do i take to the airport if i am using the round tour ticket?
The most comfortable is to take a bus from Furano to Asahikawa Airport, but it is not covered by the round tour ticket. You could save a little by taking a train from Furano to Biei (covered) and catch the airport bus from there. Biei is closer to the airport than Asahikawa.