Attention baseball fans: planning a ballpark vacation around the Midwest? In this age of niche marketing, it’s no surprise that someone has written a book for you. Baseball Road Trips is Chicago travel writer Timothy Mullin’s guidebook to the major and minor league ballparks of the Upper Midwest. The Wisconsin chapter starts with Miller Park as Mullin lavishes praise on the custom of tailgating and describes such local color details as the retractable roof and, of course, the beer and bratwurst. Sidebars include recommended side trips to area breweries, directions on parking, tips on hotels, an eclectic recommended restaurant list (Benji’s through La Merenda and Mr. Perkins) and an explanation of the supper club phenomenon. Also mentioned are Beloit’s Pohlman Field, Appleton’s Time Warner Field and other venues from around the state.