The Playbook is an essential guide for new members of all abilities, and a players' general reference.
Note this is in PDF format.
FVC_Playbook_v2.pdf
Here are a few slides showing the 4-2 Defensive system in more detail:
Defensive System 4-2.pdf
And here is a link to the downloadable rulebok from FIVB website (large document in PDF format):
http://www.fivb.org/en/volleyball/Rules/FIVB.2009-2012.VB.RulesOfTheGame.Eng.TextfileOnly.pdf