Cleaning APT Cache of only not installed packages

[dabj01]

I want to use APTonCD to make a disc for someone else who has no internet to update their system. I've installed all the packages I want them to have and have uninstalled packages they don't need. However there are a lot of packages in my cache that I have uninstalled and do not want on the CD. For example the qt libraries from when i tried out dolphin. How can i remove all the packages from my cache that are not installed. apt-get autoclean only removes outdated packages, clean removes everything.

Thanks in advance. I'll go try to answer another newbie question while i wait.