Finish all your storm peaks and icecrown quests to amass a huge quantity of money (20k or so). Spend a lot of the money on titanium gear for your tank and revenant/titanium gear for your shamans, and walk right into heroics. I didn't have to gear my team up in regular instances at all. I did a crapton of quests in 5-7 days, got like 25k gold, bought a titansteel destroyer and 4 titansteel guardians, titansteel treads, earthguard ring, earthguard chain, some tempered saronite gear and daunting gear (all crafted boe), then revenant chest/feet for shamans and went right into Heroic Gundrak and had almost no issues