Photoshop film grain plugins?

Yes, it is from Alien Skin and is called Exposure. It replicates many different color and black & white films plus it has other features such as imulating cross process film. I mainly use it for its black & white effects and prefer the Tri-X 100 setting.

It is super easy. Just load the image in Photoshop, open the plug in and apply the film you want to choose. It has a split window preview so you can see the effect before applying it to the image. Once applied to the image it is as easy to undo as any other Photoshop edit.

I'm sure the Alien Skin website can offer a good definition of its features and a list of the films that it replicates.

I like it. I probably don't use it as much as I thought but I really like the black and white effects versus desaturating an image or other techniques I've tried. If I make an image B&W I always use Exposure to do it. It is kind of expensive. I was in school at the time and got it at an academic price.