You'll be in Milwaukee at a great time of the year. Summerfest, the world's largest music festival runs form June 28 through July 8, 2007. Here's a link.
http://www.summerfest.com/
The world headquarters of the Experimental Aricraft Association is in Oshkosh, about 90 minutes north of Milwaukee. Their annual fly-in will be July 23-29, 2007, and isn't to be missed if you'll be here at that time. If you aren't going to be in Milwaukee at that time of the month, ride to Oshkosh anyhow and tour the EAA museum. It's inspiring. Here's a link
http://www.eaa.org/
Our brothers and sisters who ride BMWs are going to have their International Rally in West Bend (45 minutes north of Milwaukee) July 12-15, 2007. They are an exceedingly friendly group, and welcome riders of all motorcycles. Here's a link
http://www.bmwmoa.org/rally/rally07/rally07announce.htm
All of Wisconsin is a great motorcycling state. There are abundant opportunites for day trips in the countryside. Let me know when you'll be here and I'll suggest some rides. Also, GWRRA has active chapters and members willing to guide you on day trips, or suggest routes.
Watch teh Brewers lose a game in beautiful Miller Park, go salmon fishing on a charter boat on Lake Michigan, tour the Harley plant, ride up to Green Bay for lunch and tour Lambeau Field and the Green Bay Packer hall of Fame (this is not to be missed for any football fan). Take a long day and ride to Door County in NE Wisconsin - it's like New England.
You'll have a good time here in July.