I would go with the one on her official website man. I do not know who she is, or her signing habits, but I would think it wise to go with the one that the site says

well i seen you requested this on my thread to call them but its not a week day so i cant call until monday...and if no one on here knows the answer today i will call for you tommorow

For Naomi Judd, I have found this address, which is on her official website stating all fanmail should be directed...
Big Enterprises
1610 17th Ave S
Nashville, TN 37212

On another website there are two P.O. boxes

and on here ,there is another address that was just updated...

Any ideas on which to send to? I don't know which is most updated to and which is most reliable... Thanks!