As of 13 February 2014, nine Wisconsin counties had probate materials on line at FamilySearch.org. These are all browseable but not searchable. When I say they're indexed, I mean that a handwritten or typed index has been scanned for part or all of them. Please note that FamilySearch's own list of what's on line is inaccurate on several points, including the claim to have Burnett County.
This is a supplement to the syllabus for my 18 February 2014 webinar, "Probate Will Not Be the Death of You," for the Wisconsin State Genealogical Society. Even if you're scared of courthouses or allergic to them, you can learn plenty about probate from browsing these images.
Harold Henderson, "Wisconsin Probates On Line at FamilySearch," Midwestern Microhistory: A Genealogy Blog, posted 14 February 2014 (http://midwesternmicrohistory.blogspot.com : viewed [date]). [Please feel free to link to the specific post if you prefer.]