See exception 1a on page 9 : https://www.irs.gov/pub/irs-pdf/iw7.pdf
Form W7:
www.irs.gov/pub/irs-pdf/fw7.pdf
Instructions for Form W7:
www.irs.gov/pub/irs-pdf/iw7.pdf
ITIN Acceptance Agents (US and international)
http://www.irs.gov/Individuals/Acceptance-Agent-Program
To apply for an ITIN from abroad:
http://www.irs.gov/Individuals/International-Taxpayers/Obtaining-an-ITIN-from-Abroad
Additional publications of interest:
http://www.irs.gov/file_source/pub/irs-pdf/p1915.pdf
www.irs.gov/pub/irs-pdf/p 501 .pdf
www.irs.gov/pub/irs-pdf/p 515 .pdf
www.irs.gov/pub/irs-pdf/p519.pdf
