Esperanto: Multlingva Inform-Centro: Multilingual Information Center about Esperanto: Information in many languages about Esperant

Lernu!: Presentation of the language in multiple languages and direct communication with Esperanto speakers from countries all over the world. Features include a built-in dictionary, multimedia courses at various skill levels, and objective examinations

Uniono por la Linguo Internaciona (Ido): Official site of Ido, the international language. Site in Ido and tens of other languages