More good advice badmix.
The most important thing is training. I hope the group you belong to will train you or hook you up with a school for training. Just like badmix said-You don't want to have to be rescued to. A saying I've heard in our Fire Academy many times---Don't become part of the problem----
Don't waste money on rope equipment until you are trained on it. Utility rope to tying stuff down/setting up shelter, etc... OK. But NOT FOR HUMAN LIFE. This requires specialized training and equipment.
I'm sure if your really into this, you will get the training you will need as time goes on. Start learning the basics from your team, take more classes as you learn and get experience to more advanced levels.
Your getting some good advice on equipment here and I'm sure your team will expand on this.
You can buy all the equipment you want, but if you don't know how to use it, it's useless.