I sent LocalNet an email and this was their reply.
"Hello!
LocalNet does not offer this particular service. However, may of these types of service available online are compatible with LocalNet. You can try a google search for 'callwave' or 'call alert' to locate some options."
I found Call Alert, which is free, at
http://www.ivrsoft.com/call-alert.htm.
Thank you for all your help.