Looking for addon...

[Arick]

I'm looking for an addon that displays worth of items when you mouse over them so that I can know for how much cash i can sell my whites to npcs

[Cruzix]

Think this is one of the easier ones to find if you searched on google, its name is SellValue.

It remembers the items sell price when you have it in your inventory while browsing a vendor

[HaZzZrD]

I use Informant. Very good addon.