Hi Jessica. Sounds like you are doing something really awesome.
I'd love to work on your site.
Personally, I'd break the project down into two stages, and I'm bidding on the first stage: planning and design.
For my bid, I'll work with you to establish the exact requirements, and to furnish a visual design.
We'll talk to establish exactly what you need. I think you've got a pretty firm idea, and that's a great start. But a thorough planning stage is pretty important, and can help to avoid misunderstandings and ambiguities.
Once we've completed planning, I'll submit a draft design. I can provide limited revisions for this.
Once you are happy with the design, we can move on to the next stage: coding the design into a functional site. This will be seperate project, and will require another payment. But if you wish, I can help you with this as well.