If you are looking for something to mix in with your foundation to give it more radiance/luminosity then i would suggest LORAC's oil-free luminizer: http://www.sephora.com/browse/product.jhtml?id=P38
If you want something to dab on in certain places on your face like on top of your cheeks, cupid's bow, browbone then I would go for Benefit's High Beam : http://www.sephora.com/browse/product.jhtml?id=P12
or Make Up Forever's Uplight (not at Sephora yet but on the MUFE website)
I hope that helps!
Illamasqua's Illuminator has a pearly-white shade that works great. It goes on wet but dries quickly, leaving a high-shine, reflective finish that lasts all day or night. You can find it at: http://sephora.com/browse/product.jhtml?id=P241708
I hope this helps you.
With your light skin a would suggest the new NARS illuminator in Copacabana which is described as a glistening pearl. You can dab/place a little in specific areas or mix a drop into your existing foundation for an all-over healthy glow. Of course you can use it on it's own too.