British Petroleum Statistical Review of World Energy
The Statistical Review of World Energy is a very good source for international time-series data on energy production and consumption, with a collection of downloadable data here.
This site, which is hosted by Columbia's Socioeconomic Applications and Data Center, compiles links to various sources for data on sustainability. Access to the data is free of charge but does require creating an account to download datasets.
World Bank Environment
This World Bank site contains links to various resources, including a collection of environmental data and statistics. The Bank also has a variety of other environment-related data sources ranging from snapshots of environmental conditions to indicators of "green accounting" to data collected from specific research projects. See also the environmental data section within the Bank's data collections.
World Bank Global Economic Monitor Commodities Data
"The World Bank collection of monthly commodities prices and indices from 1960 to present, updated on the third working day of each month, as presented in the Commodity Price Data (a.k.a. Pink Sheet), published continuously for more than half a century."
United Nations Food and Agriculture Organization (FAO) Statistics
The FAO is a UN organization that is ostensibly devoted to alleviating world hunger. The FAO's collection of statistics and databases covers a variety of topics, such as water, agricultural production, and agricultural consumption. The geographic and time coverage vary by topic and database. Users can query the databases to create extracts of data of interest.