How old are these? If they have a label inside, there might be a model # listed. You could get better search results if you can find that info.
Also, I went to nike.com & did a search for white shoes .... there are lots of close styles. Are these ones that you are trying to replace, or do you just like the look of them?
Nike:
NikeStore. Shop the Official Nike Store for Shoes, Clothing & Gear
Finishline:
Athletic Shoes, Running Shoes, Basketball Shoes, Jordan Shoes, Nike Shox, Nike Air Force 1 | FinishLine.com | Search Results
Hope one of these will work out for you.