I assume it's a simple macro, help plz

[StephenMB]

Learning as I go and still brand new to WoW..... Have Mk/Dr/H/H/H - When I pull multiple MOB's it's tough to get aggro on all of them and my healer takes a beating. Im lvl 30 by the way... So how do I pull and keep all my DPS on the main tougher target while my tank aggros the other adds one at a time to get them on him and then go back to the tougher MOB? I have key "1" as my main tank attack and all my hunters main attack. Is there some macro I can do that tells the hunters so stay on a certain target no matter what other MOB I target? Currently I just TAB to next target to taunt but then all my Hunters target that MOB also...I want them ti stay on main/tougher target.

If anyone has a guide, or better a video, for the basics of this stuff I would love it!

Thanks in advance.