if you are using PS2 there is a filter called photo filter if you look under the image tab, there is no specific filter which says this is for a sepia effect
if you are not using PS2 then by degausing the pic turning it grayscale then tuning the hue to an orange tone will have the same effect.
You could also use Photoshop’s duotones feature for some beautiful and variable effects. First press Image > Mode > grayscale to drop out the colour info. Then press Image > Mode > duotones.
The first colour, black is chosen for you, use the other box to scroll through the Pantone colours. You can choose a combination of two (duotone), three (tritone), or four colours (quadtone).
You get infinitely variable effects this way. My favourite is the kind of purplish-brown tone obtained photographically with some selenium toners.