I'm not sure if this is exactly what you're asking for:
http://esomerchants.org/item-database/
It is a website that users contribute data to using this addon:
http://www.esoui.com/downloads/info2...tExporter.html
There is also this addon:
http://www.esoui.com/downloads/info3...hExtended.html
Which allows you to search your gStores in game.