I use clips like these to create branches and flower beds as well as using them for single leaves/flowers.
I have not included Normal Maps with these clips because they would become redundent as soon as the clips were combined or arranged into branches or flower beds.
To make the Normal Maps (I also use the same process for Bump Maps) I often split the image into RGB, HSL or CMYK channels. This allows me to extract veins, or other features and modify them seperatly before recombining them into a new image, I can, for example, seperate out the veins in a leaf and modify them before recombing so that the normal map will treat them as a depresion in the leaf surface. (Right click on image and save to you hard drive for reference).