the best way to do it: clipping paths. learn the pen tool in photoshop 6 or 7 (i know, i was scared of it at first too).
find a good, solid background image and stamp out anythign that you don't want in there.
then find the images that you want to paste onto the background (if it's four pictures of one person, find four pictures).
in each of the four pictures, trace the subject using the pen tool. be sure to include shadows or anything that would give away the fact that it's a clone.
make the path you just created with the pen tool a selection. copy that selection and paste it into a new layer in your background image.
repeat for all of the clones you want to put in.
now in your background image with all of the clones in separate layers, adjust the sizing and lighting for each individual in the shot. since they are each on their own layer, you can apply effects to just the one portion you are looking for.
when you've got it the way you want it, flatten the image. voila.
i will sit down this weekend and write a tutorial about using the pen tool and clipping paths in photoshop.
rob
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