Often the difference between a plain jane dress (which at times can be quite beautiful) and a second glance dress (ooooo, like that name for a dress, might use it later) is the combination of color and fabric.
I've been visiting this website, Color Collective, as it has good references for color combinations and clothing. Good for when you have an inspiration block.
But I also love the idea of a fabric journal. Gives a very tactile reference to your ideas.