Source of commodity production statistics? What would be a recommended source of historical data for commodity production amounts which is current up to the previous year or better?

For example, if I wanted to know the annual global production of steel (metric tonnes), timber, cotton, soybeans, aluminum, salt, sulfuric acid, asphalt, paperboard, wheat, kaolin, copper, silica, etc etc, where could I find that information. Note I want physical amounts (tonnes, bushels or whatever), not prices or dollar volume.
I work for Quandl and on our site I can recommend two free historical databases that you may want to check out: 

The United Nations Industrial Commodities Database, I believe, shows production amounts for various commodities like steel, petroleum, glass etc. in metric tons for different countries: https://www.quandl.com/data/UINC

The United Nations Energy Statistics Database also shows production for other things like alcohol, gasoline etc. in metric tons: https://www.quandl.com/data/UENG

When you go to each database above, just search for "production" within each database. Hope this helps!