How to install some .deb packages from cache with apt?

To create a personal repository

Install dpkg-dev, type in a terminal

 sudo apt-get update
 sudo apt-get install dpkg-dev

Create the Script to update your packages directory

It's a simple three liner:

 #! /bin/bash
 cd /var/cache/apt
 dpkg-scanpackages . /dev/null | gzip -9c > Packages.gz

Cut and paste the above into gedit, and save it as update-debs in /bin.

Next, make the script executable:

 sudo chmod u+x /bin/update-debs

How the script works:

dpkg-scanpackages looks at all the packages in /var/cache/apt, and the output is compressed and written to a file Packages.gz, that apt-get update can read

Edited: =========================================================

Create a Ubuntu configuration file for the repository

sudo touch /etc/apt/sources.list.d/mysources.list

Edit the empty file and add this line:

sudo nano /etc/apt/sources.list.d/mysources.list

And add this line:

deb [trusted=yes] file:/var/cache/apt ./

And you're done.

Whenever you put a new deb in the /var/cache/apt directory, run

sudo update-debs
sudo apt-get update

Now your local packages can be manipulated with Synaptic, aptitude and the apt commands: apt-get, apt-cache, etc.