How do I add a Phone lookup field to an In Negotiation view?

I have tried going to:

>Setup

>Customization

>Fields

>Modules List: In  Negotiation  

>New Custom Field

Then added both a lookup field and a straight forward phone field but when I apply this field to my Negoation view the column is never populated against the record...

Any help on resolving this issue would be much appreciated!

Thanks