I am happy to announce that all the articles from the First Extension Wiki site that was trashed by a hacker(s) has been recreated at the ClickWiki.
First Extensions developers Wiki - (article)
But more importantly the first article on creating a simple extension for MMF1.5 has been recreated in almost its entirety.
Tutorial - Your first extension - (article)
Thanks to Jax and Vortex2 for allowing the articles to be recreated on the ClickWiki.