Someone recently posted a question in the other Fanfic thread asking about Avatar Fanfic. I’m always surprised and flattered when people want to write in my world. Someone recently asked about writing in one of the worlds in a commercial book, and I told them that it was fine under certain conditions.
I have a short, and a long answer about Avatar fanfic, but they both amount to the same answer: No. (<- short answer)
Here's the long answer:
… because of a lot of reasons. For one, no one knows the Avatar world but me. You might THINK you know it, but you don't. You're familiar with some of the characters, but not where they're going, or why. You're certainly not familiar enough with the Goddess and there's no way you're familiar with that world — even though it looks a lot like ours does.
Avatar is a looong story. Books 1 and 2 of Establishment have a certain pacing, one that I'm not overly happy with. They are too deep, I think, and not broad enough. I'm working on that though. But I have the full story arc down, and I know how I'm gonna get to the end. But in terms of time traversed in story time, it's gonna be pretty short.
There are more books planned (and even started, in one case) in the Avatar universe. Next up after Establishment will be the Conflict stories. These will be shorter books, maybe novellas, not 50+ chapter tomes. They will be important and tell stories in the Avatar world. And things that are done, are written about NOW, in Establishment, will have (in some cases) a direct effect on events in later books.
So, until it's finished, or I decide it never will be, I cannot officially sanction Avatar fanfic. You just don't know the world that it will become. Naturally, I can't stop someone from writing whatever they want and posting it. I'm certainly not going to go all DMCA or Legal on someone who does such a thing. But don't take that to mean I'm giving tacit approval for Avatar fanfic, because I'm not.
Once the story is finished, I'll be happy to revisit the issue. I hope that I will have created a rich universe and told a wonderful, sex filled story. And at that time, I'm sure there will be room for other people's input. But that time, I'm sorry to say, hasn't come yet.
Using the Wil Wheaton terminology, I don't want to be a dick. I really am flattered. I'm just not ready for the Avatar world to be open to the public.