how to put ringtones on the iphone 4

Ringtones are known as 'Tones' in iTunes. Go to iTunes>Preferences>General> makes sure Tones is checked. The Tones folder should then appear under Library.

It is but you need to use a third party app with file share. Try this one:

http://itunes.apple.com/us/app/best-ringtone-maker-free/id394897596?mt=8

It works for me.

iTunes 11 makes it more challenging and I haven't seen this which worked for me. I took a free mp3 and imported into itunes. Used advanced to change to an acc. Dragged it (must be under 40 seconds) to desktop and rt clicked, where I changed the format to m4r (ringtone format). I dragged this onto the Tones designation (you have to make sure Tones are checked in Preferences>General) which is a drop down from the left side of itunes (where Music, Movies, Books, Tones) can be individually selected. Then I attached the iphone to the computer and let it sync. I went to the iphone, settings, Sound, apps and ringtones, and saw my new ringtone and checked it. What is missing in the instructions is the way you sync to the iphone. I clicked on the ringtone listing in Tones on my computer and dragged it to the far right and the iphone shows up just as it looks like you're going out of the iTunes window...didn't know that would happen. That is how I dropped (synced) the ringtone onto the iphone. Hope this was helpful.

I used the Freemake Video Converter to convert to Apple iPhone format (.mp4), then changed teh file extension to .m4r (thanks to SilverBear for that part 🙂). Dragged it into the Tones folder in iTunes, then dragged & dropped into the Tones folder on my iPhone 4s. Works a treat!