From Bigasoft.com:

Bigasoft iPhone Ringtone Maker is an easy-to-use iPhone ringtone creator which helps you easily convert music like MP3 to iPhone ringtone M4R, even create iPhone ringtone M4R from your personal music/movie collection including WMA, M4A, WAV, MP3, RA, AVI, MPEG, WMV, DivX, MP4, H.264/AVC, AVCHD, MKV, RM, MOV, XviD, 3GP and so on, and transfer the new created ringtone to iPhone via USB cable for you automatically.

Bigasoft iPhone Ringtone Maker can help you clip any music and video segment you like as your unique iPhone ringtone. You can assign a specific iPhone ringtone to individual contacts in your iPhone, or choose the new made iPhone ringtone to play as an alarm.

Key Features:
1. Convert MP3 to iPhone ringtone M4R
2. Make custom iPhone ringtone from music files
Any music file you love can be converted to ringtone for iPhone due to the support for a wide range of music formats like MP3, WMA, WAV, M4A, etc.
3. Create iPhone ringtone from video files
4. Transfer ringtone to iPhone automatically
The ultimate ringtone creator automatically transfers your own ringtones to your iPhone such that you can hear these fantastic ringtones when your acquaintances call you.
5. Adjust ringer volume
You can reduce or increase iPhone ringtone volume for hearing phone ring wherever you stay in a quiet room or in a noisy environment.
6. Take whole song as ringtone
Bigasoft iPhone Ringtone Maker can take music longer than 30-second as ringtone; moreover, it can take the whole song as ringtone also.
7. Customize ringtone duration
Graphical display of music files to help you set exact start and end time of the segment to hundredth of a second.
8. Listen before transfer
Listen the iPhone ringtone before conversion and transfer to iPhone via USB cable, save your time.
9. Easy to use
10. Multi-language support
Provides chooses including English, German, French, Chinese and Japanese now.
11. Compatible with Windows Vista and Windows 7
12. iPhone 3GS support