In my posts about how to level a warrior tank (most recent post here) I've mentioned the use of BoA gear. But I noticed I haven't actually said anything about which gear to use. And it might not be so strange, just use the tank ones of course! But it's not that easy, because there is no real BoA tankset out there. If you want BoA gear as a tank you have to settle for the second best option, the PvP gear. It is the only BoA gear which has any tanklike stat, and it is resilience. Resilience works like a lesser alternative to defense, but if there is no option resilience is quite good as a tank stat. It will lower the chance that mobs crit you, which is the most important aspect of being a tank, even when being a lowbie in my opinion. Although mobs only crit you about 5% of the time of their swings, one crit can do alot of damage. The difference between defense and resilience is that defense also increases your chance to block, dodge and parry and for the mob to miss you, while resilience only lowers the mob chance to crit you and the damage you take from dots.
Actually I find it weird that there's no proper tank gear to be had at lower levels. Considering that the shortage of tanks have been an issue since forever in WoW, one would think Blizzard would like to encourage people who level an alt to chose to do it as a tank by giving them some proper awesome tank gear for the job. The only reasons I see for them not doing this is either they think the resilience gear is enough, or they think you can tank well enough without tank gear at lower levels anyway. Although both these arguments are fairly true, to me it's a matter of principles. If they want people to tank, they should provide real tank gear. How come every other role gets a proper gear, and not this one? And as we will see there isn't even a complete set of resilience gear to get for a tank, as important gear pieces like chest is missing. And if you intend to be a druid tank, even more gear is missing.
In any case, resilience gear is what we've got to work with, so here it is. Everything listed here can be found at wowhead.com.
Shoulders: Strengthened Stockade Pauldrons, or of you're a druid Exceptional Stormshroud Shoulders
Trinket: Inherited Insignia of the Horde
Gun: Upgraded Dwarven Hand Cannon (nothing for druids unfortunately)
Weapon: Sharpened Scarlet Kris (nothing for druids or paladins unfortunately)
As you can see there isn't much, and this is definitely something I would like to see Blizzard implement into the game. More power to the tanks!