If anyone is looking for a good application that offers free ringtones (without signing your soul away or getting unwanted/surprise text/calls/etc.) I suggest downloading Zedge from the Playstore.
Unfortunately it's not compatible with Apple products because they need every dime you have and rarely offer anything for free, but still...
It's basically like uTorrent but for ringtones, notification tones, graphics, and games. You can upload, download, and share pretty much anything (pictures, music clips [short and long] from movies, songs, video games, shows, etc.) for free, and it's simply awesome.
(On occasion another ad will pop up on the Zedge sccreen, but hey, it's free. If I can handle getting a hundred notifications for me to play Candy Crush on Facebook, I can deal with one more on a different application.)
Not really sure about ringback tones, though...
(Personally I despise those. Did you ever think that maybe I don't want to be forced to listen to "Call Me Maybe" when I'm trying to contact you? Lol.)
*I am an AT&T employee and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.