TheShrike,
With your image reference, did you create a camera image plane, or did you map your image reference onto a polygonal plane? Eventhough I never used the Create Polygon Tool, what I do, and since for some reason my computer cannot handle camera image planes, I would map my reference onto a polygonal plane, turn on texture view by pressing the 6 key, and then go into the Lambert 1 attributes and bump up the transparancy roughly to about 25%. This allows me to see the image reference as well as being able to see the polygonal mesh I am working.
However, if you are using a camera plane, and I am not too sure if this will work, but you may try viewing that viewport in X-Ray mode. You can activate this by going to the to viewport menu and choosing Shading->X-Ray.