Neither the Message Waiting Indicator (stutter dial tone), nor the Visual Message Waiting Indicator (flashing light) functions are supported for Google Voice on OBi devices.
You can instead have Google Voice send you a text message or email when you have a voice mail message waiting.
Well that answers my question so I will just have to set up G.V. to send me an email when I get a new message, I will just have to get into a habit of checking my email for messages rather than the phone, I will get used to it just fine so thanks for the answer to my question SteveInWA.
