Installing git

Una alternativa a CVS y SVN, un sistema de control de versiones.
My way: download, extract, configure,  compile & install:
http://packages.ubuntu.com/es/karmic/git-core
http://packages.ubuntu.com/es/karmic/amd64/git-core/download

Source
I put together a more up to date upgrade sequence.
http://scoop.cheerfactory.co.uk/2009/05/14/installing-git-from-source-ubuntu/
sudo apt-get update
sudo apt-get remove git-core
sudo apt-get install tcl8.4 tk8.4
sudo apt-get build-dep git-core

wget http://kernel.org/pub/software/scm/git/git-1.6.3.1.tar.gz
tar -zxvf git-1.6.3.1.tar.gz
cd git-1.6.3.1
./configure
make
sudo make install

sudo ln -s /usr/local/bin/git /usr/bin/git

Actualized:
http://blog.avirtualhome.com/git-packages-for-ubuntu/

https://help.ubuntu.com/community/Git