Here is a web site to help you out if you decided to set one up.
http://www.payphone-directory.org/sounds.html You can left click on either of the icons to listen to a message and decide if it is right your use. To save any of the messages just right click on the icon and choose save as and then select what folder you want the file saved into.
Next you will have to either bring you answering machine over to your computer or the remote handset if using a cordless. You will need the device that contains the microphone to use as the input of the recording. Now play the recording off your computer and into the answering machine for your greeting message.You may have to play around with the volume settings on your computer or just move the mic further away from the speaker. After a few tries you will have a great greeting message to avoid unwanted calls.
Don't forget to tell your friends so that they will ignore the message and still leave you a message after the beep.
VG