And/or set up motion sensor cameras.

Too true. Loads of these stories are made up, but it's OK background noise when at work :)

Depends upon the area, there's one area I used to camp at where the deed was kept because there were some nearby people who wouldn't pay attention to when the neighbors were using their property, but would call emergency if they saw smoke, so the cops and fire department would show up and they'd start asking questions

Plus it's not hard to get a copy of your land deed. Just go to the county courthouse records department, pay your money, and walk out with it. Yes, you must have your drivers license as proof. I have a copy at my house. I live on 45 acres, that's paid for, and I'll have people show up camping in my woods. When I call the police to make them leave, most who won't leave when I ask them to, claim they're the owners. I just show the Deputy Sheriff or State Trooper (I live in the middle of nowhere) my id and copy of the deed. Case closed and they escort the intruders off of my land. In some cases the trespassers are in cuffs and leave in the back seat of the County Sheriff's Office car.