If you're looking for a meeting place or a good stop around ½ or halfway between Finneytown and South Bend, you can try Carmel, IN, which is about 2 hours northwest of Finneytown, or about 2 hours south of South Bend.
Another possible place to stop near the midpoint is Noblesville.
About ¼ or a fourth of the way, you can stop at Shelbyville, IN. This is about 1 hour west of Finneytown.
About ⅓ or a third of the way, you can stop at Franklin, IN. This is about 1½ hours west of Finneytown.
About ⅔ or two thirds of the way, you can stop at Peru, IN. This is almost 3 hours northwest of Finneytown, or a little over 1 hour south of South Bend.
About ¾ or three fourths of the way, you can stop at Denver, IN. This is about 3 hours northwest of Finneytown, or almost an hour south of South Bend.
If you drive straight through without stopping at all, the total distance is 242 miles. The distances shown above don't include local roads to get into each town, so if you're planning a long road trip, make sure you factor in traffic and road conditions, rest stop breaks, and interesting detours along the way. If you're in a rush, you can do the trip with zero stops, and your total travel time would be around 3 hours, 56 minutes.