A lot of good input, but in my opinion you dont want to do anything "Back Door" I prefer to be up front and personal. If it was me I would go to his work and get in his face, I mean nose-to-nose so that you are spitting on him as you are yelling. I have a few lines that have always worked in the past. Bottom line, I would inform him that if ANYTHING happens to your car in the future, whether it was him or not you are going to beat the $hit out of him, or worse... It only works if you show absolutely NO fear, and act like a crazy person.
Now since you say that he is a local restaurant owner, I personally find it hard to believe that it was him, but you would know better than me. At any rate I would confront him and let him know what happened.
As far as the police go, yes you can call them, and they may or may not take a report. However, if you do this and then later end up beating the $hit out of him who do you think the police are going to come looking for?
At any rate that sucks and I live in Northern California so you have one more person who would be willing to help... I had back door people who mess with others vehicles...