Wisconsin has a huge amount of public land. Not all of it is listed on the WDNR website. Especially as you go farther north, a lot of county hold public land as well. Short of getting a plat book, I'm not sure how you would research it. Maybe call a local DNR office in a county you are interested in. Definitely, the farther north you go, the less congested land will be.
(By the way, from the counties you list, you may be confusing east and west, Buffalo, Trempealeau, and Jackson are in west-central Wisconsin).
Good Luck