W-8 BEN is the
Certificate of Foreign Status of Beneficial Owner for United States Tax Withholding.
Use this form if you are claiming treaty benefits or are providing the form only to claim that you are a foreign person exempt from backup withholding.
This is a one page form and is quite straightforward to fill out.
There are about 11 categories of check boxes and about 13 areas to fill in then there is the signature, date and capacity in which you are acting.
Print out the W-8 BEN from this web site.
W-8BEN Instructions
Certificate of Foreign Status of Beneficial Owner for United States Tax Withholding Instructions.
This is a seven page instructional that gives a lot of detailed instructions about: