Different in every area, depends on the membership. We're trying to move away from meetings altogether and use Loomio for decision making https://www.loomio.org/ some places my insist officers turn up to a weekly meeting in someones house and do a secret Green Party jig before speaking. Best way to find out is to join and find out what other people in the area are like.
Hope it goes well, vive la revolution.
Depends what you want really, there's no shortage of political books out there. I've still got a long list to read myself.
Environmental Politics: A Very Short Introduction is good (the Environmental Economics book from the same series is also okay-ish but not very wide-ranging). Green Parties, Green Future is one I want to read at some point. I've also heard good things about Derek Wall's No-Nonsense Guide to Green Politics and Shahrar Ali's Why Vote Green but haven't read them myself. I'm sure there are more though.
On a wider note, there are quite a few major titles within the environmental movement, past (Silent Spring, A Blueprint for Survival) and present (This Changes Everything). Haven't got round to reading many of them.
Just been informed that there will be a used book sale for green and political books at conference too, looking forward to that.
I haven't read much in this category, but I thought Green Alternatives to Globalisation: A Manifesto by Caroline Lucas and Michael Woodin was a good read.