Warrior tanking

One of the things I really strive to do in WoW is play multiple classes and play them well. I don't want to be "that guy" who had one of each class but couldn't play their way out of a cardboard box with any of them.

So maybe not surprisingly, I've spent a lot of times on the forums and on elitist jerks learning about various classes. So far my greatest weakness is warrior tanking - I think I do really well in other situations (dps as various specs and classes is very easy for me, and tanking on my paladin is easy - I haven't tried to tank on my druid when it wasn't Black Morass so I can't really speak for my druid tanking skills XD, and healing is also something that comes pretty naturally to me).

I think part of my problem is I tend to group with people nowadays who outgear me. I am wearing mostly greens and blues when it comes to tanking (and the two worst trinkets IN THE WORLD). But I also hate to use that as an excuse, so I'm thinking that my next project will be to respec Shaeldre to protection and give some 5-mans a shot. Just need to pick my group members carefully (or make them be careful >:)) so I don't frustrate myself right back to Fury spec again.

I don't think Protection will ever be Shaeldre's main spec, but I still want to be in a position where I feel confident that I can handle tanking a 5-man instance so I can take pressure off my sister (the guild's main tank) and not feel like 1/3 of a warrior noob ;)