A few years ago Milky & I visited Blairstown, where Friday the 13th was filmed. In the beginning, you see the girls walking through the arches of The Old Mill, and we took some photos there.
Crystal Lake is on the property of the Boy Scouts and they are vigilant for trespassers for obvious reasons, so we didn't sneak in to take photos of the lake or the cabins used in filming. I'm told most of them have been rebuilt, anyway.
Creepily enough this nearby house has gravestones in their front yard, too. You can click any of the photos for bigger versions. Blairstown is nearby Mt. Hope, site of some old iron mine pits and ruins, a cool place to go hiking. Also home to the Double D Ranch (heh, heh) a nice place to go horseback riding. There's a decent diner in town, this being Jersey. So you can make a decent day trip out of it.