These are links that i used when getting the tanking gear for halvor - Also check my talent tree in Armory

This link is the best link out of them all it tells you what were you can
upgrade you gear and also were to start looking for good tanking gear

http://www.tankspot.com/forums/f97/39462-wotlk-tanking-gear-list.html

This site is also great if you are a new tank it tells you how much defence you need to cap crits (as tank you should never be hit hard )

http://www.tankspot.com/forums/f64/39474-so-you-re-heading-northrend-huh.html

This site is great as it tells you what defence gems fit in what colour sockets
http://hokage.org/node/550 - Defence defence defence gems i say

As a tank you need to know your enemy before you even meet him. This site is great as it gives you a great view
of the bosses but also tells you what the boss/mobs will do which gives you a major advantage when tanking
http://www.youtube.com/profile?user=Cityhunter0505&view=videos

Another thing to know about tanking is how to keep aggro on all you mobs the best was to do this is by marking the mobs first allowing the group to set there focus Skull is always killed first the Cross or X which should give you enough time to build up aggro on other mobs so they dont attack party members.

Aggro = Threat this can be kept up high above all other part members if you use the simple steps

1) Devastate
2) Shield Slam as often as you can
5) Thunderclap
4) Revenge (if available) causes a high amount of threat
on multi tragets keep Thunderclaping + Shockwave