How about a simple php script that just sends a mail to root when its done.

I have no knowledge of PHP, I can just
about get by with bash and a lot of help from online sources. Would
sending mail to root only appear on the pc that the backup script is run
on? in my case the server. I tend not to have to look at the command
prompt too often as most access is done via samba.

"SendEmail is a lightweight, completely command line based, SMTP email
agent. If you have the need to send email from the command line, this
tool is perfect. It was designed to be used in bash scripts, Perl
programs, and web sites, but it is also quite useful in many other
contexts. SendEmail is written in Perl and is unique in that it
requires NO SPECIAL MODULES. It has an intuitive and flexible set of
command-line options, making it very easy to learn and use."

Check it out:

caspian.dotconf.net/menu/Software/SendEmail/