Research tip
When you are doing research, it is important to know that information is usually indexed by county. So your first objective in researching a place you've never been to, would be to determine what county it is in and work from there. This is especially helpful in narrowing down an internet search.

Indiana Time zones
Remember: When you are traveling North or South for meetings or ghost hunts, during the winter, NW and SW Indiana are on Central Daylight time, so you want to make sure your aren't waiting around for an hour for everyone to show up (going N.)—or show up an hour late and miss the meeting! (going S.) During the summer, if we do hunts around Cincinnati, OH or Louisville, KY, they will be an hour ahead.

Counties in Green
Standard Time (EST); Dearborn and Ohio counties near Cincinnati, OH, and Clark, Floyd and Harrison counties near Louisville, KY. But these counties also observe Eastern Daylight Time (EDT), which means on the first Sunday in April, at 2 a.m. they spring ahead an hour along with New York, until the last Sunday in October at 2 a.m.

Counties in Red
Central Standard Time (CST); Jasper, Lake, LaPorte, Newton, Porter, and Starke* counties near Chicago, and Gibson, Posey, Spencer, Vanderburgh, and Warrick counties around Evansville. These counties also observe Central Daylight Time (CDT), which means on the last Sunday in October, at 2 a.m. they fall back an hour along with Chicago, until the first Sunday in April at 2 a.m. *Starke county is still disputed.

There have been several instances where Daylight time was uniformly applied across the country. From 1942-1945, daylight time was adopted across the nation to conserve wartime electricity. A similar measure was taken in 1973-1975 following the oil embargo of 1973. For more in-depth information you can check out: http://www.mccsc.edu/time.html#DATE

Click map for a larger view.