Third address you've posted is for sending fan mails to [b]Shake It Up[/b] and SIU is serie on Disney Channel. When Bella worked there, fans could send her fan mails but it's [b][u]not[/u][/b] her official address for fan mails, it doesn't belong to her. :) Every address you've posted is right but you posted this in [b]2011[/b] and Bella [b]changed[/b] her PO box, so her official address is posted on her [b]verified Facebook[/b]:

BELLA THORNE
C/O Persona PR
8840 Wilshire Blvd 2nd Floor
Beverly Hills, CA 90211

From what you posted, I'm guessing it's the one on Melrose Ave. {up}

sorry, which one is that? all these we're listed different places.

I would go with the one listed on her website {up}

I would go with the one listed on her website {up}

So, there's like millions of addresses for her.
1. Ms.Bella Thorne
10061 Riverside Drive
Suite 710
Toluca Lake, CA 91602
{from: [url]http://www.fanmail.biz/mboard/viewtopic.php?f=113&t=74226&start=0[/url]}

2.Bella Thorne
William Morris Endeavor Entertainment
9601 Wilshire Blvd.
3rd Floor
Beverly Hills, CA 90210
{from: [url]http://www.fanmail.biz/106003.html[/url]}

3.Bella Thorne
"Shake It Up"
Disney Channel
3800 W Alameda Avenue
Burbank, CA 91505
{from: she has a show on disney, so I guessed with this address}

4.Bella Thorne
C/O AGPR
8060 Melrose Avenue
4th Floor
Los Angeles, CA 90046
USA
{from: http://bellathorneonline.com/bella/contact-bella/}

+ I heard she was with Knight Light Management.

So where do I write too?