NREL's Life Cycle Inventory Database : http://www.nrel.gov/lci/

The US census bureau: http://www.census.gov/

The CIA World Fact Book: https://www.cia.gov/library/publications/the-world-factbook/index.html

OSHA and SIC codes: http://www.osha.gov/pls/imis/sicsearch.html

EPA: http://www.epa.gov

EPA TRI: http://www.epa.gov/tri/

EPA Chemical Risk Assessment: http://www.epa.gov/iris/

EPA e-grid Energy: http://www.epa.gov/cleanenergy/egrid/index.htm

EPA Sector Notebooks: http://www.epa.gov/compliance/resources/publications/assistance/sectors/notebooks/index.html

EPA TRI Query: http://www.epa.gov/enviro/html/tris/tris_query.html

TRI Explorer: (cut and paste into browser)
http://www.epa.gov/cgi-bin/tri.getcounties?report=chemical&scriptname=chemical&state=USA&c_year=2002&c_industry=SIC&c_chemical=&c_chemlist=
coreyear=&c_indlist=&c_usrState=&c_fips=00000&c_zip=&c_tabrpt=1&c_chk0=true&c_chk1=true&c_chk2=true&c_
chk3=true&c_chk4=true&c_chk5=true&c_chk6=&c_chk7=&c_chk8=&c_chk9=&c_chk10=

EPA LCA 101: http://www.epa.gov/nrmrl/lcaccess/lca101.html

USGS minerals info: http://minerals.usgs.gov/minerals/

US Consumption of Materials: http://pubs.usgs.gov/annrev/ar-23-107/aerdocnew.pdf

DOE EIA: http://www.eia.doe.gov/

Water and Energy Flows in U.S. Lawrence Livermore: https://flowcharts.llnl.gov/

National Emissions Inventory: http://www.epa.gov/air/airtrends/aqtrnd03/

http://www.epa.gov/air/airtrends/aqtrnd03/dl_graph.html

CDC: http://www.cdc.gov/

Environmental Product Declaration (Swedish certification for products, which would carry the EPD emblem):
1)       website: http://www.environdec.com
2)       Excel application: http://www.dantes.info/Tools&Methods/Software/Interpretation%20key%20for%20EPD%20SE(e).xls
You input the results of the EPD, and it tells you as a consumer what will be the impact if you buy the product.
 

CMU I/O website: http://www.eiolca.net/

Bureau of Labor Statistics Consumer Price Index: http://www.bls.gov/cpi/

World Bank "The Little Green Data Book": PDF

The GoodGuide: http://www.goodguide.com/

DOE Transportation Energy Data Book: PDF