I am new to OSX and am using a 56k dial-up modem. I no longer have a dedicated telephone line. I use the same line that serves as my telephone. Is there a software to download to alert me of incoming calls while I'm on the net?
You could try asking your phone company but if they did have anything software-wise it would probably be Windows only.
Looks like there's at least one subscription service that does what you want... http://www.buzme.com/buzme/service/plus.asp I know nothing about it other than that it exists.
Here's another... http://www.internetcallmanager.com/index.html This one costs $5.95 a month. I don't know if there's any stand alone software. I'm no expert, but I'm guessing it would be hard for local software to monitor calls from outside while the phone line is also occupied locally (i.e. by your modem). If you or your family have a cell phone you could always use busy call forwarding on your land line to forward any incoming calls to your cell. That's what I do. Also, since most cells have caller ID, you can decide whether or not to answer.