Resources:

Customs Ruling Search: rulings.cbp.gov

Wood Packing Requirements:  ispm15.com 

Conversation Tables: convert-me.com/en

CBM Calculator: ginifab.com/feeds/cbm/

Incoterms (2010): bfs.lt/media/images/incoterms_2010_chart.pdf

Government Agency sites:

Customs & Border Protection:  cbp.gov

Food & Drug Administration:  fda.gov

Department of Agriculture:  usda.gov

Fish & Wildlife:  fws.gov

Bureau of Industry & Security: bis.doc.gov

Transportation Security Administration:  tsa.gov

Department of Homeland Security:  dhs.gov

Federal Maritime Commission:  fmc.gov

Federal Aviation Administration:  faa.gov

Department of Transportation:  transportation.gov

Federal Trade Commission:  ftc.gov

US Census Bureau:  census.gov