I modify this addon to have in addition to the items and spell ids I wanted to know the ids of the npc.
The code was found here https://www.wowinterface.com/forums/showthread.php?t=49521 It was modified for cataclysm.
In addition to displaying the ids you can press Alt and aim at a npc it will write the id in the game chat.
If you do the same for ctrl it will write the npc name to you.
Original https://www.curseforge.com/wow/addons/idtip
the name of the idTip folder
V2 add print zone name(click for zone text) add print spell and item id(alt-pass the mouse on item or spell)