In the Warden forums on the official site there is a massive thread (
http://forums.lotro.com/showthread.php?t=245625 ) that has links to all sorts of useful and random warden-based info.
But that is a rather long list and so I'm just going to pull out some that I find could be particularly useful to up and coming wardens and non-wardens alike!
For Wardens:The Marchwarden Tanking Guide:http://lorebook.lotro.com/wiki/Warden:_Tanking_GuideTanis's Uber Virtue Breakdown:http://forums.lotro.com/showthread.php?t=260808Gambit Flowchart:http://mkweb.bcgsc.ca/lotro/For Non-Wardens:How To Use Wardens in Raids: (for Raid leaders!)http://forums.lotro.com/showthread.php?t=247910What We Wish Other Classes Knew About Wardens:http://lorebook.lotro.com/wiki/What_We_Wish_Other_Classes_Knew_About_Wardens