The apt-get package will contain the files that get installed on your system, including icons and symlinks, and it will detail where those files get installed to. Not all packages have the same contents, i.e. they don't all contain icons and symlinks to the application to be added to your desktop. In fact, I'd go as far as to say that it's quite rare for a package to install a symlink on your desktop.
So, to sum up, if you want symlinks on your desktop, it might be an idea to learn how to do it yourself. As far as icons go most are found in /%KDEHOME$/share/icons/ where %KDEHOME% is the path to the KDE installation directory. In SuSE this is /opt/kde3 but I believe most other distros install it under the /usr directory.
If you find you have no idea where they are just search for the firefox/mozilla .png file with this command at the shell
Code:
find /usr -iname mozilla.png | grep kde
That should give you some directories to look in.
Or if that returns nothing then try
Code:
find / -iname mozilla.png | grep kde