Hard - just like everywhere else.
Most property owners have been soured by deer hunters who completely screwed up the sanctity of hunting someones land. Be it bowhunters constructing stand illegally on private property or the 'army of orange' who show up in mass of 500,000 one week a year for the deer gun season largely disregarding property lines, good manners or respect for anyone else. In addition, the landowner gets tired of 'managing' the additional hunters a guy WITH permisson brings...and then of course - the guests feel THEY can bring THEIR buddies, and on it goes. So unfortuately...to many...a hunter is a hunter and the risk/reward says 'No".
Columbus in particular has a high density of weekend warriors so the 50 miles radius has been trodden upon.
In terms of fields...and I think Botiz would agree...location, location, location. It's gonna take you a year or two of seeing where birds are and what fields they tned to use before it's worth the windshield time to seek permission. I would just about guarantee you that a field worth hunting is a field that has someone hunting it already.
The good news is there's opportunity...it will just take time and gas and lots of zero's to add to your spots one at a time.
Do you have a dog?
No such thing as a stupid question, only stupid people