1. First download the packages with dependencies in your hard drive. One way to do this is using apt-get with -dy switch. For example you want to add eclipse in the addon cd. Then
$sudo apt-get install -dy eclipse eclipse-cdt
$sudo apt-get autoclean
By default these files are stored in /var/cache/apt/archives.
2. Now execute this script
#!/bin/sh
mkdir -p addon-ubuntu/dists/fiesty
cd addon-ubuntu/dists
ln -s fiesty/ stable
ln -s fiesty/ unstable
cd ..
mkdir pool
cp `find /var/cache/apt/archives/ | grep deb | grep -v /partial/` pool
dpkg-scanpackages pool /dev/null | gzip -9c > dists/fiesty/Packages.gz
gunzip -c dists/fiesty/Packages.gz > dists/fiesty/Packages
dpkg-scansources pool /dev/null | gzip -9c > dists/fiesty/Sources.gz
gunzip -c dists/fiesty/Sources.gz > dists/fiesty/Sources
echo "Origin: Ubuntu\nLabel: Ubuntu\nSuite: feisty\nVersion: 7.04\nCodename: feisty\nDate: `date -R`\nArchitectures: i386\nComponents: main restricted\nDescription: Ubuntu Feisty 7.04" > dists/fiesty/Release
apt-ftparchive release dists/fiesty >> dists/fiesty/Release
mkdir .disk
echo "Ubuntu 7.04 "Feisty Fawn" - Release i386 (`date +%Y%m%d`)" > .disk/info
cd ..
genisoimage -o ubuntu-addon.iso -r addon-ubuntu
#end of script
3. Now burn the ubuntu-addon.iso into a blank CD/DVD
4. Put the newly burned CD/DVD into the desired PC's CD/DVD drive. Open Synaptic Package Manager. There from the Edit menu selec Add CD rom and Press OK.
Now you can install all the new packages from the CD/DVD you just created. No need to download them from the net!