It is easy….
1. Choose your favourite track
2. Use an audio tool (I use Nero Wave Editor) to cut out no more than 40.00Seconds that you want to use. It may be worth adding a fade-out bit to the last 3 seconds but that is up to you.
3. Save the file as MP3
4. Add the file to iTunes
5. Right-click in iTunes and choose CONVERT TO AAC. (If it says “CONVERT TO MP3”, change your import settings EDIT > PREFERENCES > GENERAL > IMPORT SETTINGS to be AAC. Remember to switch back to MP3 later…)
6. Delete the MP3 file from itunes
7. Locate the AAC file (Right-click, GET INFO, look at the line that stats “where”)
8. Rename the file from xxx.m4a to xxx.m4r
9. Remove the entry from itunes (it won’t work now anyway)
10. Drop the m4r file into the RINGTONES folder