Skymark

I'm planning for a trip to Hokkaido, to fly from Tokyo to Asahikawa.

This website's page on transportation to Asahikawa airport states that Skymark is one of two budget airlines which connects with Tokyo. However, the Skymark's website does not seem to have Asahikawa as a destination, only Sapporo. Could the experts here confirm that it no longer flies to Asahikawa; or perhaps I'm looking at the wrong reservation webpage?

Asahikawa airport and Skymark web not wrong both.
http://www.aapb.co.jp/time/index.html
3月30日、31日のみ運航です。means "operate only 30,31 MAR".
So no operate after 1 APR.

No line cannot booking right.

Thanks, Bmetal, for your response but I'm having a wee bit of problem understanding your comments and also the Japanese website you recommended (Google Translate went wonky trying to translate). So, let me state my situation thus :

If I plan to fly to Ashikawa Airport from Tokyo on the 6 Jun 2014, my option is either the main airlines (ie. ANA, JAL which are expensive) or AirDO via Haneda.

Is my understanding correct?

Thank you, once again, for responding!!

Yes, you understood correctly. Here is the timetable on June 6, 2014.
http://flyteam.jp/airline_route/hnd_akj/flight_schedule/2014/06/06

ANA does not flight Tokyo to Asahikawa either, your only options are JAL or Air Do. An Air Do it not exactly what I would call "budget", it's basically the same price as JAL. If you are traveling to Japan with a Oneworld carrier, your best option is to take advantage of JAL's "Yookoso Japan" fare

http://www.jal.co.jp/yokosojapan/

If not, the cheapest option it to take Jetstar to Sapporo and then to Asahikawa by train.

Oh, I see Air Do has a codeshare with ANA, so you cna use ANA's Experience Japan fare also on Air Do flights :

http://www.ana.co.jp/wws/us/e/wws_common/promotion/experience_jp/