I looked around a bit for you and found this thread:
http://www.google.com/support/forum/p/v ... 3a5d&hl=enI have created a pretty nifty, fully fledged, python module for the google voice API. Currently you can place calls, send sms, download voicemail/recorded calls, and check the various folders of your Google Voice Accounts. You can use the Python API or command line script to schedule calls, check for new recieved calls/sms, or even sync your recorded voicemails/calls. Works for Python 2 and 3. Project available at http://github.com/justquick/python-googlevoice/
That is in Python however, but it might be possible for you to port to PHP. Here is the current location:
http://code.google.com/p/pygooglevoice/Google Voice for Python
This project aims to bring the power of the Google Voice API to the Python language in a simple, easy-to-use manner. Currently it allows you to place calls, send sms, download voicemails/recorded messages, and search the various folders of your Google Voice Accounts. You can use the Python API or command line script to schedule calls, check for new received calls/sms, or even sync your recorded voicemails/calls. Works for Python 2 and Python 3
I also just found this one:
https://github.com/aaronpk/Google-Voice-PHP-APIThat one says it is a Google Voice PHP API, maybe what you are looking for:
Google Voice PHP API
An API to interact with Google Voice using PHP.
Currently the API can place calls, send and receive SMS messages, and download transcriptions of voicemail.
Feel free to implement new functionality and send me your changes so I can incorporate them into this library!
Note: Receiving SMSs and voicemails is mostly unnecessary via this API since Google now allows SMSs to be forwarded to an email address. It is a better idea to parse those incoming emails with a script.
Let me know how it goes, that would be awesome if you could achieve this through Google's free service.
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