Transfer share to Petaluma from SFO Feb 2016

My colleague and I are travelling from Australia for the Mindfulness Tools programme in Petaluma in Febuary 2016. Is anyone else interested in sharing the transport costs from San Francisco to Petaluma and back? We will be leaving from the vicinity of Union Square on Friday the 4th of Feb and plan to return to the same area at the end of the 5 day Mindfulness tools programme.

Hello are there any ride-shares from San Francisco airport to Petaluma TDI course in March, OR has Oasis arranged for a bus. Thanks