How do I make an iTunes song into an iPhone ringtone?

Unfortunately, I have taken a vow of not supporting teeny-bopper music, so I can't help you with this query. No, I better not say that as my 11yo daughter will never let me hear the end of it: she's quite a fan of Miley Cyrus and her alter ego Hannah Montana too. In fact, we listened to Miley all weekend as we drove around town, somewhat to my consternation. :-)

Nonetheless, I'll show you how to accomplish your goal with a different song. Okay? Same end result, just, um, a bit less pop.

My song of choice? The 80s new age group XTC and their song Senses Working Overtime. If you don't remember it, well, that's okay, you're probably younger than I am.

The first place you need to go is into the Apple iTunes application on your Mac or PC. Then find the song you want (I checked and they have "Life's What You Make It" for $0.99), just as I have done here:

Click "Buy Song" and a few seconds later you'll see the song downloading:

Once it's downloaded, just click on "Purchased" under the "Store" list and you'll see your Hannah Montana song, along with any other songs you might have purchased.

Now right-click (or, if you're on a Mac, Ctrl-click) on the song:

and choose "Create Ringtone..."

Now the lower half of the window opens up and shows you a waveform of your song, along with some basic buttons and options:

Experiment with selecting a specific portion of the song: you can click and drag the edges of the blue box to make the segment longer or shorter. Remember, a ringtone is a very short segment of music played over and over: with the "gap" setting you can specify the amount of quiet between each loop.

Tweak, fiddle, then click "Preview" to hear how it'd sound as a ringtone.

When you're done, well, what to do? It took me a few seconds to realize that I needed to make the window wider! When I did:

There ya go. The button desired is "Buy". Yes, you need to buy the rights to make a ringtone separate from buying the rights to listen to and enjoy the song. For another $0.99.

Once you do so, now you'll find a new entry in your "Ringtones" area:

Almost done. Now just plug in your Mom's iPhone, then click on the "Ringtones" tab and indicate that the phone should sync Ringtones with the computer, and sync her phone. The final step is to assign a custom ringtone on your iPhone and you're done!

Good luck with that. I hope your Mom's happy next time you call her while she's in an important business meeting! :-)