Another good option is Ringtons for iPhone, a tool that allows you to create your own iPhone ringtone. It's free to download, and it has thousands of ringtones to choose from. The app also lets you create your own soundtrack, record your voice or import other audio. You can then adjust the pitch, bass, and other parameters, and add a fade in and out. You can even record your own audio, so you can use it as a ringtone.
Zedge is another great place to find free ringtones. This site offers a great collection of user-generated ringtones and has a search feature. But it isn't all about the ringtones though; you can also find notifications, message tones, and Christmas sounds. Zedge also has apps for iPhone and Android that offer better interfaces and categories for you to browse. Another good option is Notification Sounds, which offers ringtones that sound similar to the sounds that come preloaded with your phone.