This is a great use of OneNote.
First you'll need a device like this:
http://www.dynametric.com/cassetterecorderpatch.asp
You connect it inline with your telephone handset and connect the jack to
your PC mic input.
Then you can use the record functions within OneNote to record the audio
from the telephone when you have calls. The audio will be indexed to your
handwritten notes.
By the way, you should check the laws in your state to see if it is legal to
record phone conversations. Some states only require the permission of one
party (e.g. you), some states require permission of both parties on the call.
