Discussion never happens in a vacuum; start building it, and people will want to talk about it (mostly to tell you what they think you're doing wrong at first, but it's better than nothing).

Writing a non-trivial language remains a daunting task, and like any daunting task, the people who spend the most time talking about it are the ones who spend the less time building it.

Grab a few books on the subject, and dive right in :)

"the people who spend the most time talking about"

Where?

Is my impression so far that people that do this is more the theory (like lambda), or isolated people that eventually push his project. But wonder if exist a kind of community about this.

If is only talking about, is fine for me. Is not the lack of books, tutorial, code, is the lack of other people that also have tried it so is possible to compare notes, ie, if I wanna do a videogame I can find groups that talk about it (and see the conversations). That is very valuable, specially when starting.

clicky: http://lambda-the-ultimate.org/