Asterisk PBX

I recently discovered another piece of Open Source software that I hadn't examined much before. It's called Asterisk, and it's designed to let you create your own telephony system. The problem is... it seems to be very complex and poorly documented. Although it's been around for a long while, it looks like no one has taken the time to build solid documentation - so I bet it's been reserved to hackers and linux masters, excluding those who don't have years of experience playing around with these types of systems. Might be fun to use if I can get it to work, though. According to the site: Asterisk is an open source framework for building communications applications. Asterisk turns an ordinary computer into a communications server. Asterisk powers IP PBX systems, VoIP gateways, conference servers and other custom solutions. It is used by small businesses, large businesses, call centers, carriers and government agencies, worldwide. Asterisk is free and open source. Asterisk is sponsored by Digium. It would be cool to use this to automate and simplify things, maybe even create our own professional sounding office voicemail system without paying hundreds a month.