Here is a link to an article that talks about why vintners don't list ingredients. And grapes are often a crop that is doused heavily in pesticides and herbicides so if you react, it might even be to a residue of something toxic left on the grapes themselves. When I buy wine, I buy organic. But you might also have luck by going to a local winery near you where you can ask them about their ingredients. I also presume that the more commercial the process, the more likely the ingredients lists were determined in a lab rather than just being good, old-fashioned wine making.
Thanks for the linked article, Naturechick. It's totally correct in it's premise that we normally consider wine 'unprocessed' and elemental. For those of us in the world who are trying to be mindful of what we are putting into our bodies aside from just gluten (and mindful of what effect massive production/agricultural processes are doing to the ecosystems), it's a great starting off article to investigate it further. Organic wine - I'll have to look harder for it.