Type
%appdata%
In to the address bar of My Computer, or Windows Explorer. (or the Start > search [Vista] Start > Run [XP] box)
This will bring you to the 'Roaming' folder under which you should then click on 'Adobe' then 'Dreamwever9' - and that should show you your configuration folder.
The full path is:
[Vista]
C:\Users\your_user_name\AppData\Roaming\Adobe\Dreamweaver 9\Configuration
[Windows XP]
C:\Users\Neil\Application Data\Roaming\Adobe\Dreamweaver 9\Configuration
Not sure what a Mac path would be, but %appdata% will get you most of the way there.