Going nuts changing Mac Mail to field

I'm trying to send with the correct name in the "to" field of my Mac Mail emails.

The person's name for this discussion is let's say jsmith@somewhere.com. When I put this into my "to" field in Mac Mail, OS X changes this to some common name it has used previously, only thing, that name is wrong (misspelled).

I made the correction to my contacts with the correct name, but everytime I use jsmith@somewhere.com, Mac mail does not reflect the change it changes the email address to the incorrect/misspelled common name, not my correction.

WHERE DO YOU CHANGE COMMON NAMES OF RECIPIENTS???

Is there no way to edit the name you want to appear instead of their email address?

This is driving me nuts, any help apprecited.