You will not find any OpenOCD binaries here, src releases can be downloaded from here.
If you are using Ubuntu then OpenOCD can be installed using apt:
apt-get install openocd
Note that this may be an old version, so you may be better off building from source.
For those windows users Freddie Chopin makes available various binaries.
Also note! if you check out the latest version of OpenOCD from git you should know that it is work in progress and it may very well be better for you to get a slightly older version.
The official OpenOCD git server is hosted at http://openocd.sourceforge.net.
If you want to get actual work done and not play around with OpenOCD development (fun as it is…), then your best bet is to get the latest recommended version from your hardware debugger supplier.