check out
http://www.x100p.com/ they have a x100p card that works with Asterix for $30.00. I have purchased a couple of these cards and they work flawlessly.
http://www.x100p.com/products/FXO.php
fxs - connects standard telephone to ethernet for VOIP
fxo - connects VOIP servr to standard telehone line so VOIP phones can call out over standard telco lines. if you want to use asterix as an answering machine for home on your standard phone line for instance
Asterix should be able to talk to your VOIP provider directly
There are quite a few software VOIP phones available.
Check the asterix wiki for recommendations
http://www.voip-info.org/wiki/index....erisk#Hardware
There are several