Hey Fonz,
I'm in Madison, WI. Unfortunately, Wisconsin is not exactly dirtbike heaven. :ugg: The closest legal, public place to ride that I know of are:
Dyracuse: North of the Dells and north of Adams/Friendship on highway 13. Two MX tracks plus some decent single track. Fee required.
Nielsville: North of Black River Falls on highway 10. A very good single track loop of about 17 miles. No fee.
CMJ Raceway: Also near Black River Falls. This is a private deal--you have to buy a membership to ride unless you are riding one of the organized events. MX track and a 3 or 4 mile hare scrambles single track loop.
Your bud might consider joining the Madison Motorcycle Club (dues are a whopping $5 a year, but you gotta be an AMA member--which we all should be anyway). He could make some contacts/riding buddies.