Because Goolgle Talk uses the open XMPP/Jabber protocol, you can of course connect pretty easy with agsXMPP to this service.
here is a small sample how to connect to the Google Chat service
Small Google Talk Overview:
agsXMPP supports all instant messaging features of Google Talk. But the Google Talk service currently supports only very basic IM features like presence and chat.
The voice chat features are not supported yet, because Google's XMPP voice protocol is not documented. Once the protocol is documented we may add support for it.
Google added SRV-Records to their DNS-servers now.
Under Win32 you can set
The library will find the Connection
server by looking up the SRV-Records in the DNS-server.
You don't need to set the ConnectServer Property then, because the library does
this automatically by using the SRV-Records.