With the season one finale of Legend of Korra all wrapped up it's going to be some time before we get new Avatar action.
Don't fear. Legend of Kaito is the next best thing to the actual cartoon and should alleviate the symptoms of Avatar withdrawal! (This is my opinion only of course.)
Legend of Kaito deals with the Fire Avatar at the end of Aang and Korra's cycle.
Legend of Kaito is written as to (hopefully) be able to exist within the Avatar universe we all know and love, and heavily infused with the works of Miyazaki.
Give Kaito a try!