No, this is not an "old story"; it is your misunderstanding of how Google Voice works. Think about it: you don't have an inbound telephone number, so how can someone call you?
Google Voice isn't a freestanding telephone company. It's an inbound call forwarding service. You can either select a Google Voice inbound telephone number from Google's pool of available phone numbers, or you can port in a mobile phone number.
Once you have a Google Voice inbound telephone number, people can call you on that number. Google Voice then
forwards those calls to the forwarding destinations you select, on this page:
https://www.google.com/voice#phonesYou can add up to six different 10-digit telephone numbers, and optionally, you can forward calls to Google Chat. OBi devices emulate (act as) Google Chat clients.
If you don't have an inbound Google Voice telephone number, then you can still make outbound calls, but there will be no caller ID number sent with your calls, again, since you have no phone number.
So: Go to the page I linked above, and click "Get a Voice number". To be eligible to claim a Google Voice inbound telephone number, you need to submit a forwarding phone number. This number needs to be located within the 48 contiguous US states, and must be with a traditional land line telephone carrier (e.g. AT&T, Comcast, Charter, CenturyLink, Frontier), or one of the "big four" mobile phone carriers. The forwarding number you submit must not have been previously submitted to claim a GV number.
Here are my complete instructions for using Google Voice on an OBi device:
http://www.obitalk.com/forum/index.php?topic=8560.msg56460#msg56460Learn more about Google Voice:
https://support.google.com/voice/#topic=1707989