The example shown here are based on installation of Shibboleth ”out of the box” (rpm and yum) with RHEL6 64-bitars and apache http-server 2.x. If your system is based on rpm (RHEL, CentOS, SUSE, Fedora etc.), you should be able to install without any problems. If your system is pkg-based (Debian, Ubuntu etc.) you use apt-get and in the case of Debian or Ubuntu you don't have to install a separate repo.
You should note that the libcurl-version in RHEL6.x or higher (or CentOS) doesn't work with shibboleth. If you later install shibboleth according to the documents here, there will be a proper libcurl installed i the /opt/shibboleth directory. In order to make the installation of this work, you have to see to it that SELinux isn't in enforced mode. It should be put in disabled or permissive mode.
Install Apache httpd with yum:
# yum install httpd.x86_64
# yum install mod_ssl