With Bagnon you can double click the spot where it says your characters name and type quest to highlight all the quest items in your bags or for the sake of sanity and not searching use the handy daily macro

Code:
/use Writhing Mass
 /use Darkmender's Tincture
 /use Improved Land Mines
 /use Flesh Giant Spine
 /use Copperclaw's Volatile Oil
 /use Ebon Blade Banner
 /use Tainted Essence
 /use Diluted Cult Tonic
That one is stolen from a thread somewhere on here, can't find it atm, however it covers nearly every Icecrown daily quest.

Anyway good luck