Hello Lior

Here is a quick one I found that might lead you to what you might be looking for http://www.webdesign.org/photoshop/drawing-techniques/v-day-greeting-e-card.19644.html Also I have seen many similar written tutorials on http://www.deviantart.com that you can do a simple search like greeting card tutorial a majority of the tutorials on deviant art are written or in PDF format

Hope this helps some

I have found at DA a few here  http://www.deviantart.com/browse/all/resources/?q=+greeting+card+tutorial  : not so inspiring :(