I recently authorized a new computer but none of my music is there. How do I get it there?

You need to copy it there from your old computer:

http://support.apple.com/kb/HT1727

or for content purchased from the iTunes Store, download it again:

http://support.apple.com/kb/ht2519

By the way, if you want email responses to your questions, just subscribe to the thread ("receive email notifications"). Most people here do not wish their email addresses known and hence will not reply to you via email.

Regards.