Need help regarding usb to rj-45

Hi,

I'm collecting information to start my project,
my first step will be to make my PC playing a wave file to the caller after answering the call after 6 rings. (what programmation language do you suggest for phone(and VoIP), .net, C+, perl, Ruby ???

I will need you suggestion on below comment,
I believe that the best thing will be to use my USB port to adapt to the telephone compagny, to do that, I will need an usb to rj-11 adapter similar or equivalent to :

**broken link removed** (but at lower cost and this one seems that netgear are not producing them anymore).

Waiting for some hints, suggestions from you guys....

Brgds-Charlie

First hooking anything home made up to the phone line can damage the phone companys gear and they will be unhappy and may seek legal action or at the very least a disconnect.
Best solution is a old fashoned modem, they are pretty easy to use and have an AT command set that can send a string to a serial port when the phone rings, some even support call display. Should be cheap and easy to find on ebay.