Depends on how you want to do it. If it is a print document, you can convert
it to web format, and upload it to a subfolder on your website, and link to
it from your site. Reference: Convert Your Publisher Newsletter for Use on
the Web:
http://office.microsoft.com/en-us/publisher/HA010563151033.aspx

Alternatively, and probably easier would be to convert it to a PDF file,
upload it and link to it. You can convert your newsletter to PDF with a free
converter at www.primopdf.com

DavidF