Does anyone know how i would go about placing an image on top of an existing image in the exact same place for about 500 files?

Basically, i have a bunch of thumbnails, all 200x200 and i also have a small media player graphic that i want to put on the bottom of all these thumbs so they look like 'movie clips'.

Anyone know how i would set this up as a Photoshop batch job instead of having to manually place the graphic on the thumbs myself?

Regards,

Lee