Welcome to the forum and the world of OC.
I encourage you to read this: http://www.wisconsincarry.org/legal.html
You can find a pamphlet regarding Wisconsin gun rights here: http://www.wisconsincarry.org/pdf/OCpamphletR16.pdf
I carried in PDC on Sunday just two days ago, I was in McDonalds, nobody called the police. OC is 100% legal in WI if you avoid the five restricted places (Cars, Bars, Government Buildings, State Parks, School Zones).
Car: Unloaded and in a case.
Bar: Prohibited (Any place that serves for consumption on the premises
Government Buildings: Prohibited
State Parks: Prohibited
School Zones: Prohibited (1000 ft from edge of school property unless on private property).
McDonalds, Culvers, Starbucks, WalMart, Auto Parts Store, Sporting Goods Store, Church, Bank, etc. ALL Legal UNLESS they post a sign.
LEO knows OC is legal, but they won't tell you that because they DON'T want you to exercise your rights. They may come and harass you, but nobody has ever been charged with Disorderly Conduct or Disturbing the Peace for the mere open carry of a firearm since the AG's memo April 20, 2009.
Hope this answers you questions, if not ask away, we are here to help.
Again WELCOME and Carry On!