Open the .mp3 file you would like to use as your ringtone in itunes. Find the section of the song you want to use by noting the start time and the stop time. This time should be limited to under 30 seconds. The example in the video I chose to use the portion between 00:27 and 00:54.
Step2
Once you know the start and stop time of the section you want to use, you now need to right click on the file in itunes. This will open a menu, select "get info". Navigate to the Options tab and input your start and stop times. If you want to make the ringtone louder then you can increase the sound volume here as well. Click Ok when done.
Step3
Next you will need to go to the Edit menu and select preferences. Click on the Advanced tab and then click on importing.
Step4
In the drop down box that states "import using:" select AAC encoder. In the "setting:" drop down box select custom and select 32kbps. Click Ok.
Step5
Next you will right click on your .mp3 file and select "Convert Selection to AAC". itunes will then convert the selected portion of the .mp3 file into ringtone format, which will be .m4a. It will save this file in your itunes directory. Once saved rename your file, removing any spaces that may be in the title. The uploader sometimes doesn't like spaces.
Step6
Point your internet browser to http://www.funformobile.com, then click on the link for the ringtone uploader. Enter your phone carrier, phone number, and add the ringtone you just created by using the "Browse" function. Click the "upload" button and a text message will be sent to your phone with a link to download the new ringtone, enjoy!!!
Tips & Warnings
This is 100% Free, there is no cost for the itunes software, it is a free download. There is no cost for the use of the uploader. There are other uploaders available on the net if this one is not to your liking.
Keep the ringers to less than 30 seconds or risk large files and also your call will probably go to voicemail before the ringtone is finished.
Authority 
Comments
smashtheqube said
on 6/21/2008 It's much easier to just use Mobile17.... they even support the iPhone and most others as well. http://mobile17.com
writetruth said
on 5/17/2008 Great helpful information and video post!!! 5 Stars ~!~
Romba said
on 3/28/2008 An easier method is to use this free tool http://makeownringtone.com
richardchan said
on 3/27/2008 Scott, thanks for the video post. A few at work were making the changes while listening to the video!
showpup said
on 3/25/2008 I didn't know you could do this. My son's gonna love this tutorial! Thanks.