I am sorry for taking so long to reply. I am not exactly sure what you want to do, but I use Google Voice this way;
I have a US local number in Google Voice. This is forwarded to my 'home' phone number inthe US, which is actually an IPKall number (
FREE IP Calling with IPKall).
The IPKall number is linked to my Voxalot account.
This means that any calls to my Google Voice number will ring at my Voxalot account.
Regards. MG.