In Wisconsin, you can register to vote on Election Day at your polling place. You can find your polling place by clicking here: https://vpa.wi.gov/. You can also register to vote at your municipal clerk's office until 5:00 p.m. today!
Check out what you need to bring here: http://gab.wi.gov/elections-voting/voters/registration-voting. Here are your two options:
2. IN PERSON: Register in the municipal clerk's office up to 5:00 PM or the close of business whichever is later on the day before the election. (For the September Partisan Primary, that date is Monday, September 13, 2010 and for the November General Election that date is, Monday, November 1, 2010.) Note: After the BY MAIL deadline, an elector registering in person in the clerk's office is required to present acceptable proof of residence as outlined below.
3. AT THE POLLING PLACE ON ELECTION DAY: If you wish to register to vote at your polling place, you must bring proof that you have lived at your present location for at least 10 days preceding the election. For purposes of voter registration, acceptable forms of proof of residence must include:
1. A current and complete name, including both the given and family name; and
2. A current and complete residential address, including a numbered street address, if any, and the name of a municipality.