I didn't see anyone mention the DNR's maps.
http://dnrmaps.wisconsin.gov/imf/imf.jsp?site=mgdlands
This may not zoom in as close as others mentioned but it has all the layers that tell you where DNR land is and all the other DNR map layers that other maps don't have such as deer zones, turkey zones, and public hunting boundaries.
Between the DNR map and the others mentioned it's amazing at the info you can get without even leaving the house. It's kind of exiting and scary to think about where this tech. is going in the future. Big brother is watching. I looked up my home on several map systems and can date most of the pics by the vehicles in my driveway and landscape/gardens. These are all free map sites, you can buy a lot better versions. Google Earth has the free site and you can upgrade it for something like $300 if I remember right. Makes me wonder what big brothers version can see.
American by birth, hunter by choice.