Feral Bear Obtainable Set

I just recently traded for a 70 druid that I'd like to go feral with for tanking. It came in balance, so I've swapped to Resto to get into dungeons. When I leveled my druid back when BC was new, I just built up through instances which were pretty easy.

I guess my question is, what should my gear look like before I respec and start trying to get into dungeons? And, if possible, what activity should I prioritize to reach this goal?

What I mean is, do I need a certain amount of stamina, defense, armor to start tanking in dungeons where I can really begin to get the gear that I need?

The two most important things you can get is the crafted Strength of the Clefthoof set (that will last you a LONG time) and the mace from Cenarion Expedition exalted (will last even longer). Your most important target first up is to get 390 defense to be uncrittable in heroics - you can get away with less for normals. The above gear will help a lot in getting there. You can use some pvp pieces (typically bracers, belt, boots) to get uncrittable, but don't go overboard with that as you'll gimp your armor and dodge.