The best place to start is with an accurate description of exactly what you want your shot to look like. Then you can make a plan to execute your design. Your question is so vague I can't give you much of anything that will help you with your design. I can give you a few basics though.
Each picture would either have to be a separate layer or you would arrange them in a grid on a single layer and then use Card Dance or Shatter to have them fall. You can also use pictures as particles in some particle plug-ins and make them fall that way.
If you go with each picture on a separate layer you can achieve better results if the layers are 3D and you introduce some tumbling as they fall. If you are After Effects CS5 or CS5.5 then you have FreeForm included and you can use that plugin to bend your picture layers to make them look more realistic. If you want to go with pictures falling from above and landing on a floor or a table then you can try particle systems that support a floor or set keyframes for single layers so that they act the way you want them to. Expressions can help with randomizing tumble and roll as the layers fall into position and scatter on the table.
If you want the most realistic simulation of pictures falling and landing on something that has collisions and scattering based on physics then you will want to do the animating in a 3D app that supports those features. Blender (http://blender.org) is an open source 3D app that supports those features and has fairly easy to understand and use integration with After Effects. C4D Lite comes with AE now, but the Lite version does not have the editing or animation engines to support designing falling pictures completely in C4D Lite, but you could do a limited version of the effect with it just fine.
Give us a detailed description or even sketch a couple of storyboards with a pencil to help us understand exactly what you are trying to do and we can point you in a better direction. You'll need a fairly solid background in the basics of animation and the AE UI to successfully complete the project. If you are very new to AE please learn the Basic Workflow by going through some basic instruction.
You need to be more specific.
Do you want them tumbling downward? Do you want them to land?
First thought: simply place your images in in various places in 3d space and have them slowly rotating (you could apply a time expression to some rotation parameters), then parent them all to a null object and animate it moving down. The result would be a bunch of images appearing to fall past the camera.
For $32, I'd just buy the template...
Yar, chump change.
But there's Foam, too. Overlooked and under-appreciated. You can create a pre comp of the still images and use the emitter to squirt them out one at a time. Not nearly as elegant as the template but it's already on your machine. However, it will cost you far more than $32 in your time figuring out how to located good tutorials for Foam and then experimenting.
Yeah I would normally buy the templates, but at some time you need to figure out how to do these things on your own for future work.
This link might be a nice head start.
I also would recommend you to watch some 3D layer tutorials. These might be useful creating the falling 3D effect you want to achieve. If you have any further enquiries, please do not hesitate to contact me.