Nike sunglasses aren't the greatest, so I don't think you're going to find many people interested in collecting or discussing the things. eBay or Craigslint might be your best bet.
nightsx2- thanks for the input. Do you know of any general athletic eyewear forum? I know lots of cyclist and triathletes that use Nike sunglasses .. i agree with you, oakley is way better and far more interesting..
Why avoid eBay? There are millions of potential customers who are cyclists and athletes. I think eBay or Craigslist is your best bet. You can always list that you're willing to ship on your craigslist ad.