addon to find what char has heirlooms?
 

as what the title says [;

altoholic is a good one for this. Just install and log into each of your characters and open their bags and banks and character screens etc and it will fill the saved variables tables with their information. Then, regardless of what character you are on you will be able to see the contents of their bags/banks/equipment/skills etc.

/agreed. Altoholic may be a bit large, however, when you have multiple toons it really is the best way to keep track of who has what.

It will pretty much keep tabs on all info for your toons. Gear/inv/currency/reps/skills....so on and so on...

For a standalone AddOn which provides that functionality only, I suggest BankItems.