I'm afraid there isn't much interesting to be found at the airport. There are a lot of shops, but they all same the same, and the selection is not very good. There is one supermarket in the public shopping area of the airport that has a bit of a better selection, but it's very expensive.
If you have time, it's better to travel into the city. Some good shops:
Ton Overmars, situated in the western part of the city. Very good selection of bordeaux, vintage port, alsace etc. Most of the better stuff is online. Has the best pricing in the city.
Wijn Antiquariaat, in the city centre. For old and rare wines. Not cheap, but prices are sometimes negociable.
Cave Rokin, small shop, situated in a cellar. Very broad selection.
Hope this helps!
(And if you have time for a glass of wine while in Amsterdam, let me know!)