Ido For All (a big grammar of the language Ido) now available as huge pdf file

Right here. Recently there's been some activity on Idolisto with a new user of the language, and that's when the link came up. Apparently it's still a work in progress but having it as a single pdf is many times better than the previous alternative, which was searching through various Geocities and other sites for a good grammar to learn the language. Paul Bartlett writes the following here:

Excellent! I have had two different versions of "Ido for All," neither of which was formatted very well. This PDF version seems to be the best yet. This plus the KGD seem to be an effective introduction to the language (the latter for, shall we say, technical reference).

The KGD is, of course, the Kompleta Gramatiko Detaloza di la Linguo Internaciona Ido (this link is also a pdf), the complete grammar of the language, written entirely in Ido.