Telephone answering mechine service c#

Hi All,

I am looking for code written in .NET that provides connection between application and telephone.
So that - the telephone will return a code according to input code that it get's from the user.

I'll be happy to get even a little help - if you know something that relate and can help me!!

Thanks.

p.s.
I heared about TAPI but I need an example of using it by getting service from the telephone.

http://www.codeproject.com/KB/IP/devangpro.aspx

http://www.sharewareconnection.com/p...ne-decoder.htm

http://www.tapiex.com/PhoneToneDecoder.htm

http://www.brothersoft.com/phone-ton...der-29541.html

http://www.torry.net/authorsmore.php?id=3897