Although out of the way (it's 250 miles from the Twin Cities and 190 from Des Moines), the "Field of Dreams" site in Dyersville, Iowa, is so popular that the last time I visited, there were tourists from Luxembourg and Australia at the field. Best to visit when the corn is high so you can recreate Shoeless Joe and the White Sox stepping through the stalks. Be sure to bring your glove and, if possible, your father.
Next, cruise over to Indiana, the location for a surprising number of great movies about virtually every sport: cycling with "Breaking Away," basketball with "Hoosiers," football with "Rudy" and baseball with "A League of Their Own."
Two very old ballparks in the state's southwest corner are featured in "A League of Their Own." The home field for Geena Davis, Madonna and the rest of the Rockford Peaches was Huntingburg, Indiana's League Stadium, which was built in 1894. Evansville's Bosse Field, which was built in 1915, served as the home for the Racine Belles. Located at 23 Don Mattingly Way, it is currently the home for the Evansville Otters of the Frontier League, so you can catch a game there while yelling at players that there is no crying in baseball.
Indianapolis' former park, Bush Stadium, was where Hank Aaron played for the Indianapolis Clowns of the Negro League, and it also doubled for Comiskey Park and Crosley Field in "Eight Men Out." The stadium was converted into apartments recently, but much of it was preserved.
Indiana doesn't have a monopoly on movie sites, though.
Another great destination for baseball movie buffs is North Carolina, where "Bull Durham" was filmed. In Durham, you can visit the old Durham Athletic Park, where most of the baseball scenes were filmed, or play pool at the Green Room, where Nuke told a just-released Crash about his big league call-up, or walk past Annie's house. You can also go see the current Durham Bulls play at the new Durham Athletic Park, which has a snorting bull atop the scoreboard.
Better yet, go to the delightfully artsy town of Asheville, North Carolina, where Crash hit his final home run while with the Asheville Tourists. While you're in the state, visit some other great minor league action in Greensboro, Hickory, Winston-Salem, Burlington, Charlotte, and ... well, just about everywhere Crash ever took a bus.
And if you have time, call in sick to work right now and hurry down to Birmingham, Alabama's Rickwood Field, which hosts the annual Rickwood Classic next Wednesday, June 24. This old gem is where Willie Mays started his career with the Birmingham Black Barons (and more notoriously, also where Bull Connor worked as a radio announcer). The 104-year-old park has been so carefully maintained that scenes from "42" and "Cobb" were filmed there.
I'd include "Major League" and "The Natural," but alas, the ballparks where they were filmed (Milwaukee County Stadium and Buffalo, New York's War Memorial Stadium) are torn down. But you can visit some minor locations for "The Natural" in Buffalo, including the Ellicott Square Building and All-High Stadium, which stood in for a Chicago hotel and Wrigley Field in the movie. If in Buffalo, you should also visit the Anchor Bar, where the Buffalo wing was created.