Google Voice iPhone

Your google voice number cant be using your ATT number as the source.
Mini x2, iPhone 3G, iPhone4, Air, iPad Mac OS X (10.6.6)

can you please elaborate? is there a way to get it done etc....
Macbook Pro Mac OS X (10.5.7) 4 GB ram 512 Graphics

If you have a plan that gives you A List (#s you can call or receive calls from free), you can set Google Voice to display the GV # to caller ID instead of the actual callers #. Do that and add your Google Voice # to your A List.
17" iMac Mac OS X (10.6.6) iPhone 3G, iPod Shuffle, iPod Nano, MacBook

I have the 450 minute plan, Im trying to eliminate having to pay at&t anything more then the $30 a month for my unlimited internet, in short, no A-list, Im pretty sure theres a workaround I just cant figure it out
Macbook Pro Mac OS X (10.5.7) 4 GB ram 512 Graphics

If thats the case, then youll have to go with something like skype. Maybe forward your Google Voice # to skype. But youll have to pay skype for minutes in that case, which could end up costing you more than just paying AT&T to begin with. Google voice is not a voip service in the same sense that things like skype are. Its a forwarding service that uses voip to move calls across the internet to the local points of presence.
There is no way to receive a phone call on your phone without using minutes if you dont have something like a-list. Youll have to go pure VOIP and im not aware of any VOIP services that are completely free to and from people who dont use their service. IOW, if you can get grandma to use skype instead of a phone, you can talk to her for free. Good luck with that.
17" iMac Mac OS X (10.6.6) iPhone 3G, iPod Shuffle, iPod Nano, MacBook