If like me, you become dissatisfied with the stock collection of sounds supplied with the iPhone as ringtones or alarms, Apple leaves open a way to create and install new ones of your choosing.
When creating ringtones for the iPhone there are a couple of things to be aware of. Firstly iPhone ringtones can be no more than forty seconds long and secondly must be saved using Apple's ACC sound format, which places the m4a extension at the end of the file. The m4a extension is simply replaced with m4r and presto, you have a ringtone. When a sound shorter than 40secs plays, it will loop for the time limit set by your telecoms provider. Annoyingly, there can be a slight delay audible with some loops played on the iPhone despite sounding fine in a sound editor.
The m4r files are added to the iTunes music library and are then synced with the iPhone whenever you sync next.
Sounds used for SMS Text notifications are not easily editable by iPhone users. SMS sounds are stored in a different part of the phone and are saved as .aiff sound files with the extension changed to .caf.
Changing the length of your iPhone's ring time
The default ring time before my iPhone diverted to voicemail was very short, maybe just shy of fifteen seconds. The ring time is not defined within the iPhone's Settings control, it is set by your service supplier, in my case o2. To reduce the chance of missing calls because I couldn't get to my phone fast enough I needed to extend my ring time to 30 seconds.
initially i wanted to describe the method i used to extend my ring time here on this page but realised that not every supplier uses the exact same method, which can cause confusion. Instead I recommend using Google or Yahoo to search for "iPhone ring time + (your supplier's name)" to find instructions on your supplier's web site. There are often forums on telecoms supplier web site's where this subject is frequently discussed.