Ubuntu Guide shows you how to access GetDeb.net packages in Ubuntu-Software-Center in Ubuntu 11.04
1.) Run this command in a terminal window to add the repository GPG key:Access GetDeb.net packages in Ubuntu-Software-Center in Ubuntu 11.04
wget -q -O- http://archive.getdeb.net/getdeb-archive.key sudo apt-key add -
2.) Open Synaptic Package Manager, then click to Settings -> Repositories. In Other Software tab, click Add the GetDeb source for Natty:
deb http://archive.getdeb.net/ubuntu natty-getdeb apps