It contains setup guidelines for few OS/distribusions , ie. freebsd, redhat / ferdora / centos , debian sun solaris etc. By following step by step, you would be able to get snort up with web interface call BASE (Basic Analysis and Security Engine).
I was following the one for fedora and centos, and successfully installed. That pdf covers from the beginning what to includes when linux installation, what dependencies to solved, changes of iptables, uses SSL(https). The installation is quite long, but by following precisely, you would be able to get the simple IDS box done.