I ran a LFG pug of DTK on my Druid farmer the other day, first time I've tanked on him (up to this point have quest leveled on him only, in order to farm ore/herbs while leveling).
Unlike my Prot War at this stage (who was much more overgeared at this level), my druid was rage starved the entire time. I was using rage as fast or faster than it was coming in on all the trash pulls (boss pulls were ok).
Further, I found initial pulls challenging, since I usually had zero rage at the start. I'd run up and start putting FF on every mob, then start swiping and growling when I had the rage for it. But the rage buildup in those first few seconds was excruciatingly slow, esp with pug dps that didn't wait.
I'd certainly appreciate any advice or tricks to help with this.
I won't comment on your gear since i know that while leveling you got to use what's available to you (which may not be very many things).
Also, BIG TIP: gather your venture coins, and buy yourself this: http://www.wowhead.com/item=38365 you'll thank me later