Ka Neng Au, Business Librarian and creator of the International Business LibGuide at Rutgers University, has given permission to link to his guide and the extensive list of sources on International Business that he has compiled
Don't overlook reference books.
REFERENCE BOOKS WITH WEBSITES
Economic Report of the President Ref./HC 106.5 .A272 Contains table on international statistics
Statistical Abstract of the United States Ref./HA202 .S8 Includes a section on Foreign Commerce and one on International Statistics (online is available for free from 1879-2012; more recent vols are in the reference collection)