You can do this a few of ways, you can use a 3d library like away3d then have a surface on the model that allows an image to be 'molded' to it,
this will give you an idea of what can be done, select some images from your hard disk, click on the image button(1 or 2) then select an image for that holder, it will display on any 3d object you choose.
You can use a library like as3dmod http://code.google.com/p/as3dmod/ which has a bender utility which enables you to 'shape' an image
http://gumbo.flashhub.net/flip/ this will show you the strength of image bending with as3dmod.
There is also pixelbender, this is more complex as you need to write code to create filters that will 'bend' the image. But there may be something in the pixelbender gallery. http://labs.adobe.com/technologies/pixelbender/
Just note the 2 examples I gave you for away3d and pixelbender will not have sourcecode available, I just linked the examples so you can see that the image manipulation is possible with flex.