Great Ocean Road tour?

[Kristina]

Hi,
i'm from Germany and I'm planning my trip to Australia (in February) right now. I'd like to ride the Great Ocean Road by bike. As I am alone, I'd like to join other people and book a tour. Do you have an idea which travel agencies offer such a tour and how much it would be (approx)? It seems to be quite difficult to organize that from outside Australia. Do you also know if it is possibel to do the tour from Melbourne to Adelaide? So far I only found information for the other way around.
Thanks for your help.
Kristina