If you want it in a jiffy, then you can try using the following plug-in:
http://www.digieffects.com/help/FilmDamage.html
But if you want to create it yourself, then you'll need photoshop to create some of the elements you see in an old film (i.e., burned edges, streaks, splotches). I would suggest though, that you work with after effects to make the tweaking faster and more flexible.