Links
The Rugby Continuum is the structured rules applying to Rugby Union up to the U13 age range and the latest version can be found here:-
http://www.rfu.com/TheGame/Regulations/RugbyContinuum/ContinuumRulesOfPlay.aspx
U19 variations covers the laws that are varied from U13 to U19 and the latest version can be found here:-
http://www.rfu.com/TheGame/~/media/Files/2010/TheGame/Regulations/RFU%20Regulation%2015%20Appendix%202.ashx
The internet is a wide and varied source of information both in quantity and quality as I am sure any coach is discovering but there are a series of coaching vignettes from arguably the greatest living British Rugby Coach - Sir Ian McGeechan, and the link below take you there for a wide variety of drills and exercises - enjoy!
http://www.sirianmcgeechan.com/smarterrugby.php
...and finally, it would not be a new season if we didn't have some tinkering from the IRB to try make sure that referees are contually put on the back foot and front row forwards are destined to quizically scratch their heads - check out the latest directives (clarifications they like to call them) here:-
http://www.rfu.com/TakingPart/Coach/IRB_Law_Directives.aspx