personaly, id rather not shoot him, i would turn his face to putty. wait for him to come in the house, and beat the hell out of him. do check him for weapons, maybe you will get lucky and he will have something on him. knife, gun, pointed stick, whatever. if he does stop fighting back, you really need to stop even though you will definatly want to keep going. the second he stops fighting back or gives up or whatever, chill out. now if he tries to escape, do what you have too to keep him there. if he gets out and then calls the cops your screwed. if hes in your basement/bedroom/kitchen, hes screwed.
also, ontop of the no trespassing signs, put his name clearly on the sighs. a, people driving by can see his name and see it attached to the no trespassing signs. b, you are explicitly banning him from the premesis. there should be no reason for him of all people to step on your property. period.
honestly, if i fealt a real threat, i wouldnt hesitate to kill him. but barring him pulling a knife or gun on you, you would end up in jail. if it is really worth it, then that is your choice, live with it.
though it sounds good, you havent seen him in a few days, so maybe he got the point. or maybe he knows your up there. i would scoure neighborhood lookin around for cars that didnt fit in and anything suspisious. make sure hes not around earlier in the day scouting you out.
and for the paintball thing, i use to play alot. i really dont recomend using that on someone. the only way i know that wil actualy slow somone down is to shoot their face, and i wouldnt do that. i have played games of pain endurance, and you have no idea how many shots someone can take at close range if they get their adrenalin pumping. a few times we emptied our hoppers into each other from about 15 feet away, and then reloaded........and we didnt wear 5 sweatshirts or any silly bs like that. i played in a tshirt...you would have to blind the guy to stop him if he was determined. trust me on that.