Are you asking how some armor pieces say something like "Bracers of the Tiger"? That's an item that drops off of mobs in the game, it's not something you can craft or enchant. The suffix "of the <Insert Type Here>" denotes the stats you will find on the armor.
See a full list of equipment suffixes on wowwiki:
http://www.wowwiki.com/Equipment#Item_Suffixes