Synaptic just gives me version 1.7.1, but I want version 1.7.3 without the need to download and build from sources.
Debian and Ubuntu often do no track the absolutely latest minor revision of a package that is actively developed unless there are significant feature fixes or security updates (and even in the even of such changes they will often backport the update for the significant change to the revision they do carry rather than picking up a whole new revision. This is particularly true of Debian/Stable and Ubuntu/Released in general and Debian/Testing and Ubuntu/Next close to release time (when they are in a "feature freeze" state).
To get a later version you have a few options:
- Take the risk of using the later release of the distribution (i.e. Debian/Testing or Ubuntu/Next - Squeeze and Natty respectively at the moment) even though it is still officially in testing. This is not generally recommended, especially for production environments.
- Use Apt Pinning (see https://help.ubuntu.com/community/PinningHowto) to take just the packages you want from the later revision while keeping the rest of your system at the current stable/released level. This is less trouble-prone and option 1. You may still need to do a compile step if LibC has been updated significantly between the releases, but this is still easier than using the upstream source as you get the Debian/Ubuntu tweaked version (they sometimes tweak initscripts and related utility parts to better fit with the rest of their system layout and chosen standard tools) and apt/aptitude can bring down updated source for you when there are updates in the repository.
- Compile from the upstream sources as honk suggests. This will get you the latest and greatest stable (or bleeding edge beta/alpha) version, but it more effort at the outset and the onus will be on you to monitor the project for security updates and other reasons to need to recompile.
Ubuntu/Natty currently carries 126.96.36.199-2 (which probably means "188.8.131.52 with at least two back-ported updates from later revisions"), the same as Debian/Queeze.
You could also try the version from Debian/Sid (though this is currently the same version) but this is not recommended. "Unstable" is given that name for a reason - packages may be broken at any given time as it exists specifically to find significant breakages before packages are promoted to Testing.
A way likely to work would be downloading from upstream and running the usual
$ autoreconf $ ./configure --prefix=/PATH/WHERE/YOU/PUT/YOUR/STUFF $ make install
inside the unpacked source directory.
Since in your edit you now explicitly write that you do not want to build from source and want 1.7.3 tagged on 2010/10/21 things look differently.
Ubuntu's git package seems to come directly from Debian's and Debian just migrated 184.108.40.206-2 to TESTING a week ago. You might have some luck with asking for a version bump in the Debian bug tracker, and could directly use that package in Ubuntu then.
After having added following line
deb http://ftp.de.debian.org/debian squeeze main
/etc/apt/sources.list I was able to install Git 220.127.116.11 using Synaptic.