Flying in about 11:30 p.m. is there a cot area for sleeping till early morning for next flight?

Not that I'm aware of.

https://www.sleepinginairports.net This gives places and info on where to sleep in different airports.

Depends on airport, ask the carrier or look up airport online fir more info. CVG does

I am not aware of one. I don't think they have any spaces like that.

Not here, unfortunately. Too small of an airport.

I don't think so