How can I make a song into my ringtone? I have a new iphone 3GS.

Replace the m4a extension of a sound file with m4r.

Or open m4a file in Quicktime, cut the bit you need,

then just "save as",

Then rename the .mov to m4r!

Copy the m4r to itunes.

Check ringtones are sync'd.

And your done.

Type "iphone ringtones" into the Google search bar. You will find several ways.

This correct, but it will ably work if the ringtones are 30 seconds or shorter.

*only work, stupid iPhone autocorrect