Remember to keep the length of all ringtone clips under 30 seconds or iTunes will not transfer them over to your iPhone.

1. Open iTunes and find the song you want to turn into a ringtone
2. Right-click on the song and select “Get Info”
3. Click on the “Options” tab
4. Check the radio button for start time and enter the time in the song where you want your ringtone to start. Check the radio button for stop time and enter the time in the song where you want the ringtone to end. Make sure that the duration of the ringtone you selected is UNDER 30 seconds. When you are done click OK
5. Right-click on the song again and select “Create AAC version”
6. Locate the file you just created on your computer. You may be able to do this by right-clicking on the file and selecting any variant of “show file” or “show in windows explorer”
7. Replace the .m4a extension with .m4r. Double click on the file to automatically add it to your ringtone collection in iTunes

Notes

• Delete the shortened file you created from your iTunes library
• Remeber to return the start and stop time settings on the original song back to default

This is the most helpful tutorial I found:

Materials Used:

• Magnetic screwdriver
• Paper clip or sim card tool
• Suction cup
• Spudger
• Adhesive strips
• Replacement iPhone 3G OEM Glass Digitizer Screen
• Hairdryer or Heat Gun

Personal notes:

• When using the suction cup to separate the glass from the housing, you need to pull very firmly. However, do not pull too far open because the digitizer is still attached by three cables.
• When separating the frame from the LCD, be very careful when prying. Only pry from the sides and that one corner mentioned in the video.
• If you’re using a hairdryer, you need to heat the glass for NO LESS than 5 minutes. Use a rag or pot holder when peeling the glass off the frame because it gets very hot. Make sure not to warp the shape of the frame.

Before

After