I have looked up on ways to get to Hokkaido from within Japan (particularly from Tokyo or Osaka) or even directly to Hokkaido first before travelling to other parts of Japan, but they all seemed rather expensive. Taking the train seems to be the most popular way to get to Hokkaido, but the the train ticket is pretty expensive. This is only transportation. I will be travelling to Japan in February and the accommodation during this time at Hokkaido isn't cheap too because of their winter season.
Are there other cheaper alternatives to travel from within Japan to and tour around in Hokkaido?