Honestly the guy is not doing anything wrong. I know you are thinking that he is shooting on your lease but until that time, you are peeing in the wind getting upset. Now, if you want to waste all of your time trying to catch him instead of hunting, go ahead that is your choice. But if you want to catch him, that means you will hunt that area to much along with him, rendering the area pretty desolate due to pressure,.
Now it sounds like you have IDed a potential hot spot on your lease that is near your neighbor's property. You want to even politely get in his face about the stand, I will guarantee that you will not be tracking any wounded deer through his property that made their death run across the line.
To resolve this continuing debate about hunting too clsoe to property lines, it is only gonna be a matter of time before we start having state laws that say you can't hunt 200 (or any other number) yards from an adjoinging property. Now everone is gonna be pissed