It will cost you approximately $4.75 if you take I-65 to 80/90, then the Skyway, across three toll booths as of May, 2009. For a two-axle vehicle, it will cost you: 1) Indiana Toll Road (Gary East):...
The only place you will find toll roads are in Illinois, especially in the Chicago area. The cost depends on your travel route. For example, to travel I90 through Chicago, the toll would be $4.20.