Publisher 2000 user here:
The page length can be made any length up to 20 feet; yes, feet. (I have a
page that is 48"
http://www.vanusa.org/events/index.html )
If you have an existing website created with Publisher you can,
File
Page setup
Page length, enter the length in inches desired.
Note: if you create a page length of 30" and only 20" contains text and
images, only to the lowest text or image box will show when visited.
This will require you to move the existing information up to realign. Just
gather all with the mouse and move it up or do a Alt key and up Arrow. The
Alt + Arrow works best for keeping the content in its proper original
centering location as the original.