A good ringtone maker will cut a small portion of a video or song into a ringtone. The tool supports most audio formats, including MP3 and WMA at https://klingeltonkostenlos.de/lustige-klingeltone-kostenlos/. It also has an option to set the start and end positions and save the segment as an MP3 file. You can even use the same ringtone on several different mobile phones. If you don't want to spend too much, you can download Ringtone Maker for free to create your own mobile ringtones.
To find the right ringtone, browse through the sites below. Tone Tweet is a site with over 130,000 free ringtones to choose from. You can browse their lists by category or by popularity. You can also search for ringtones by keyword. Tone Tweet supports both iPhone and Android devices. The service is fairly new, but it has a decent collection. A preview mode lets you preview the ringtone before downloading.