There is another thread with people sharing google voice invites, but if you're not lucky enuff to get one by asking, you can submit a request directly to Google.
https://services.google.com/fb/forms/googlevoiceinvite/
It takes about a week or two to receive it.
https://services.google.com/fb/forms/googlevoiceinvite/
It takes about a week or two to receive it.