A lot of members take part in Nano, infact some are taking part in Camp Nano.
It is good too keep a stable of ideas (plot bunnies we call them), but it's also good to finish that first draft and go back to make it better. There are very, very few who can write a story of any length in one draft.
You've obviously already looked around and found some places you think can help you - Techniques and World Building. Roving Crits is another place you can use to improve your writing.
There are a lot of us here who love to participate in Nano each year. So much so, that some of us are doing the Camp Nano's, as well.
Taking that first draft and revising it is another skill set. Take your time going through the site. There are a lot of places to help you on your way. Also, please post any questions you might have. We're a friendly bunch, and we'll be glad to help point you in the right direction.