How to download a package?

[- <radsky@ncia.net>]

This may seem like a stupid question but how do you download a Debian
package?
(Yes, I'm a really low level newbie)
 My hangup concerns these preliminaries before performing a
download.....

 1.   Should all downloads be done by  root user or can any user do it?

 2.   What directory should be set as the active directory in the
command line?

 I've done a lot of web searching, read many books and haven't found any
information about preparation BEFORE downloading a package..  I have
downloaded a few packages as root user and downloaded to root's home
directory ' /root' but haven't yet tried installing because it just
doesn't seem right to do it from  /root for fear of screwing up the
system.  I know how to move a package to a different directory if that
will help, but to which directory?

Is /root a good directory to download into or is there a better choice?

It seems that Debian has some good commands for downloading packages but
here again, what preliminary preparations such as mentioned above are
recommended?

Am I tilting at windmills?