Does not look like there is a wealth of replies.
It might help if you could post a link to an example.
Gimp does not have a 'macro' function where you can play-back a series of actions. There might be a script somewhere that does what you want, a look around and I did not see anything obvious.
Possibly, providing the images have a constant size you could use ImageMagick in a batch file. (or a bash file if you use linux)
I'm no expert but this screenshot shows how it might be done just for the perspective. There are other functions that will emboss and enhance. Once a batch file is set up then it is up to you to provide the base and top images but after that processing is automatic.http://i.imgur.com/nERFc.jpg
My advice, if you want to try ImageMagick is to ask on their forum, They are very helpful, will have better info than me and might even make you a batch file.