Hi Amy,
Thanks for stopping by. To my knowledge there is no such photoshop filter (great idea, though) that makes a photostrip instantly with the click of a button. However, photoshop is very capable of creating faux-photostrips. (see our magazine and movie sections for lots of great examples).
The most basic explanation of how to do it in photoshop:
1) scan an actual photostrip to get proper dimensions and borders
2) take your images and paste them (or clone them) into each of the four frames of the scanned strip
3) alter color and levels to match the original strip
The challenging part about getting it EXACTLY right is to figure out a way to replicate the texture of the photobooth paper -- which in recent history (last 50 years) has a matte finish made up of hundreds of tiny raised bubbles. This could be done by overlaying a semi-transparent layer of the bubble pattern taken from an area of the orginal image.
Good luck, and let us know how it turns out.
-Tim