There is a free way of making custom ringtones for iPhone using only iTunes Mac. However, you can only follow this method to make iPhone ringtones using DRM free music in iTunes library and the ringtone has to be 30 seconds or less. If you want to custom a .m4r ringtone with protected iTunes M4P or DRM protected WMA music, you’ll have to turn to a DRM removal software to turn it DRM free first. What’s more, if you are fond of some audio/sound clip from a video file and want to set it as your iPhone ringtone, the iTunes method fails to help too. What’s going to do next?
Aiseesoft iPhone Ringtone Maker comes to the rescue! This piece of Mac iPhone ringtone maker software can help you turn virtually any music/sound source into iPhone .m4r ringtone. It can also trim audio clips from video files (in all popular video formats) as iPhone ringtones. Now let’s take a look at the detailed steps:
Step 1. Download Aiseesoft iPhone Ringtone Maker, install and run it. ( free download )

Step 2. Load Music
Click the “Browse…” button to locate your music with which you want to make iPhone ringtones and click “Open” to load it.
Step 3. Trim iPhone Ringtones
Drag the “Start” and “End” sliders to get the exact part of music from which you want to make an iPhone ringtone. Or you can input the exact beginning time and end time in “Start Time” and “End Time” boxes. Then you can click the “Play” button to pre-listen to the ringtone.
Note: If you want to transfer the ringtone directly to your iPhone, just connect your iPhone to your Mac and check “Export to iPhone” in the program. If you just want to output it to your computer, click the “Browse…” button on the right of “Local Output File” and specify the output folder.
Step 4. Generate iPhone Ringtones
After you have done the above three steps, just click the “Generate” button to start making iPhone ringtones on your Mac.
To share my experience! Article Source:http://www.articlesbase.com/software-articles/how-to-make-custom-christmas-iphone-ringtones-on-a-mac-1602315.html