Here is a list of additives permitted in wine in the EU. Many are used in U.S. wines as well: http://www.morethanorganic.com/additives-in-wine
Here is an in-depth list of additives, and what they’re used for, allowed in the U.S.: http://www.alicefeiring.com/blog/2010/11/-approved-wine-additives.html Blogger Alice Feiring says, “Remember while most people for their terroir-driven wines just stick with the usual; yeast, bacteria, acid, enzyme & sulphur (tannin gets extra points), there’s a whole lot more they can add.”
And, here is a thoughtful report on what’s going on with labeling in the U.S. today. http://blog.wblakegray.com/2011/09/wine-producers-arent-allowed-to-use-100.html#more
One more story on additives: http://www.alicefeiring.com/blog/2011/10/the-winemakers-elixir.html and http://www.toastedoakinc.com/