[App_rpt-users] Phones and Google Voice

I need to be pointed in the right direction on where to read how to do this or a little help. Is it possible to use my already established Google Voice account for auto patch on the repeater? Also I'd like to be able to have a few voip phones on my server. So I can dial an extension to monitor the repeater or dial an extension to call someone on my network. Outbound calling to a POTS line isn't needed.