I know I need to get forms signed when I shoot on private property, but what about a public place? - I'm going to be shooting in a city park. Will I need someone from the city to sign a release form? Or do I just need permission? Who should I talk to?
Since it's a public place all you would need is a permit. You'll have to talk to your local municipalities to issue you a permit or Guerrilla style it.
But I've never heard of a public location release form.
A permit is the way to go but try to fudge it on a private property. you'll have more freedom. the insurance can be costly on public grounds where you can sometimes exclude it with a private property.
a little tip: have them sign in and sign out if you get insurance or not.