iRinger is a very simple program that allows you make ringtones for your iPhone in a second!
iRinger Download
Just run the executable and select import song, the program already chops the song into the 30 secs. All you have to do is select the the section of the song by dragging it. Then select Export when you are satisfied with your ringtone and it automatically puts it into iTunes. Hook up your iPhone and sync and now you have 30 second ringtones for your iPhone
Note I am not using the current version of iTunes all though it should still work, this program also only works for iPhones 1.1.2 and above...
