Demi Lovato and Ariana Grande -- it's music madness!! And we mean that only in the best way possible. Get excited because these two fabulous ladies are set to collaboration on a song together. Demi hit up our friend's radio show, Zach Sand and the Gang, and she confirmed this info. She said QUOTE 'we've already talked about it. I love her so much. She's so sweet and so talented. I'm definitely going to collaborate with her.' Woo hoo -- this is going to be awesome. And it's perfect timing for AG to work with Demi since Ariana just got put in the top spot on Billboard.com's 2013 Mid-Year Music Awards for Best Newcomer. Congratulations!! Plus, Demi's album debuted at number-3 on the Billboard 200 -- which is oh-so-impressive. And both artists are STILL in the top 100 songs on iTunes for Demi's Heart Attack single and for Ariana's The Way song. .