I have a good reference, which is even available online, but something tells me you will cry : the wikipedia page on the [Théorème des fonctions implicites][1] is more complete than its english counterpart!

Notice that they're refencing a Lang book... so perhaps that will do better.

  [1]: http://fr.wikipedia.org/wiki/Th%25C3%25A9or%25C3%25A8me_des_fonctions_implicites