Do the Akuna Bay ride on Sat morning (6:45 at the shop). They usually have three groups, and noobs can roll along in the C group getting tips on group riding before progressing to the more testosterone filled groups. It's a tough ride, but good fun.

The Tue-Wed nite rides start out easy for three laps then all hell breaks loose. Frenetic pace lines on both nites and sprints on Wed. Not for the inexperienced or faint hearted.

[edit] You need to be covered by insurance so I guess you need to be a member of some club, and they also like you to wear a turramurra jersey so they know who's in their group.