There's no ringtone library on Itunes 11.0v. Those links are outdated. I think apple is trying to make us pay for the ringtones. I guess this is how apple is treating their loyal customers. That's why I don't have Iphone, I'm android guy. I'm just helping my wife how to get ringtones. Please, let me know how to make your own ringtones?
You would have sorted it out by now.
1. Go to EDIT =>REFFERENCE
2. Under General, tick TONES, then you will be able to see TONES folder...
To create ring tone from mp3.
1. Make sure your mp3 file playback duration is about 30 sec or less.
2. Add it to your library as you do with music.
3. Under MUSIC folder, select SONGS
4. Find the mp3 file you want for ringtone, right click it and find CREATE AAC VERSION
5. OPEN window explorer, browse to MY DOCUMENTS/MY MUSICS (XP) or Library/my music (Win 7), there should be iTunes folder in there, find the mp3 file... and change the file extension from [.m4a] into [.m4r]
6. Back to iTunes, add [filename.m4r]
Now you should have rinetone under TONES folder in your iTunes.
Great Youtube video shows how to make a ringtone.
It's for Windows machines, but I figured out how to do it on the Mac using the video.
Make sure you delete the new AAC file you create (watch the video to learn how to create the AAC file), or the ringtone won't show up on your phone when you sync.