I'm a brazilian rustacean as well, when I get some time (famous last words), I'm planning to give a Rust mini-course at Unicamp. If anyone makes a presentation in portuguese, do share! Translating the book and keeping it updated is quite an effort, I think it will be more worthwhile after we get more traction in Brazil, at the beggining we just have to assume people are confortable reading english and focus on increasing awareness of the language, with talks, presentations, blog posts.
IRC is not a very good communication channel right now because the volume is very low, a forum, mailing list or blog would be more appropiate. Rust on the rocks is a good place to focus the efforts, it ranks well in search engines. However it's kind of a mess right now and not very up-to-date, it needs to be more open and have better instructions for contributors.