So you really want to hear your music or something else obnoxios when your phone rings but you dont want to have to go through iTunes to get it into place here's the skinny on how you do it. Heres what you need:
The first part is to get your hands on the iRinger program (http://www.iringer.net/), download and install the program. Then once this is done go a head and double click on the icon. Once you have gone through all of the work of getting it installed. Once the application has opened you should see a window that looks like this. So from this point the first thing to do is to select your music, to do this click on the import button. Once you have clicked it you will get a message box to select your music. Once you are done and your music has been loaded into the software you will see this. This is the point where all of the magic happens. To modify where you want the clip to start you just click and drag the image of the sound file found below the window title and above the 'starting at' portion. Once you have done this select the amount of time that you would like to make the ringtone for by using the slider for the Length in the lower right hand side of the window. From this point you can also set wether or not you would like to fade in the clip or set the volume. At anytime in the process you can click the 'preview' button and you will be able to listen to your ringtone. When you have selected everything and you are ready to be finished click on the export and you will see this window. From this point you select the directory that you would like to export the item to change the title then click the 'Go!' button. After a few minuetes of churning the software will say it's done. From this point the next time that you sync your iPhone you should have your new ringtone.