I installed and run OpenBSD and I wanted to install git but there were no repositories for OpenBSD. What should I do if I want to install some programs with pkg_add?
You have to add one or more mirrors to your /etc/pkg.conf. You can add multiple mirrors by using the += notation.
installpath = http://ftp5.eu.openbsd.org/ftp/pub/OpenBSD/%c/packages/%a/ installpath += http://ftp2.eu.openbsd.org/pub/OpenBSD/%c/packages/%a/
%c and %a are variables that get replaced by the release and the architecture of your installation. That way you don't have to upgrade your config file after every release.