Better than any of these is to go get a webcam. Set it up in your window to cover your driveway where you park your car.
Finally, there are any number of small, magnetically triggered screamer alarms. Some of them are small enough to fit inside the fuel door.
Remeber that your objective is to get PROOF, not revenge, so that you can take it to the cops.
BTW, in addition to stealing gas, the thief is also committing criminal trespass under Ohio law, which means he could get time in the local jail, and he'll have a criminal record.
Cops and courts are hitting hard on gas thefts these days as it gets more and more common and expensive.
BTW, if you want to get MEAN, you could disconnect the fuel lines from your tank, then fill it with kerosene or diesel...once he'* totally f***ed up his motor on stolen fuel, you clean the tank out and hook it back up....