Google Voice can ring my iPod Touch

I have iPod Touch G3, 32GB. It is OK when use Skype. But I want to try call free, so use Google Voice.
To make iPod Touch works with Google Voice.
1) Have an earphone with microphone connected with iPod Touch
2) Create a TruPhone account and install the software:
3) Create a Gizmo5 account:
4) Sign into your Gizmo5 account
4a) Note your Gizmo5 phone number
4b) Configure Gizmo5 to forward all calls to SIP using “” as the address
5) Sign into your GoogleVoice account
5a) Create a new phone called Gizmo5. (Settings \ Phones)
5b) Enter your Gizmo5 number like this example: +17475551212
5c) Under Phone Type choose Gizmo5
You can now recieve calls from GoogleVoice
You can make Google Voice calls using mobile web page:
The call is looks like from GV ? Gizmo5 ?TruPhone at Ipod Touch. Then GV connect you and the other one.