In Hancock County you'll find the small city of Findlay, as well as part of Route 30, the old Lincoln Highway. You'll also find a ton of farmland, with the occasional ghost town at an old crossroads. The ones I've researched are listed here.
Cannonsburg
Union Twp.
A reasonably large town in its day, Cannonsburg was centered at the intersection of Township Road 34 and County Road 12, and stretched a couple of miles to SR 103. A hotel at SR 103 and CR 12 was a known way station on the Underground Railroad. The main intersection, that of TR 34 and CR 12, was occupied by a blacksmith's shop on the southwest corner and a school building on the northwest. Just a mile and a half to the south, the AC&Y railroad line ran alongside Cannonsburg.
Harris City
? Twp.
Named for founding father Perry Harris, who laid it out on the New York, Mahoning, and Western Railroad in 1888. It consisted of 150 lots on a dozen village streets. The plat was withdrawn in 1901.
Lewisburg
Blanchard Twp.
Also known as Louisburg. William Powell, Michael Shearer, and David Millham platted this 40-lot town on April 10, 1851, at the current intersection of US 224 and SR 235. It survived until February of 1880, when it closed down for good, but not until after it had acquired a dry good store and several residences. Never a post office, unfortunately.
Moffitt
Blanchard Twp.
Twenty-two acres were set aside for the creation of this town in 1889, on the American Midland Railroad line. A post office was placed there in September, 1895, only to close in 1917. For a while there was an express office in Moffitt. Today the railroad is gone, but you can see a cluster of trees where the old Moffitt park was.