Pre-built tarballs are available for download from the XenSource downloads
page:
https://www.xensource.com/downloads/
Once you've downloaded the tarball, simply unpack and install:
# tar zxvf xen-3.0-install.tgz
# cd xen-3.0-install
# sh ./install.sh
Once you've installed the binaries you need to configure your system as
described in Section 2.5.