Spawn, Sydo and Phloggy

I checked on the website and just followed the instructions when I did it, you should have an account toolbox you can go into, go into that and there should be a link to your webspace :)
 
You'll probably need an FTP program.

http://filezilla.sourceforge.net/ is the one I use.

Then you'll need to connect to your ISPs FTP site. It's probably something along the lines of ftp://ftp.yourisp.com.au, although it may not be (mine isn't)

When you should be able to use the username and password you use to log in on and get your email with.

Then the ftp program is pretty easy to work out. It's just navigate to the file, then double click, then presto-chango, files uploaded and ready.