I'm thinking that the first one maybe makes it sound like the books are only for Spanish speakers? Or am I nuts?

Para. . .*de* ninos would me BY children. . .

Okay, so it's 'los libros para ninos en espanol' versus 'los libros en espanol para ninos,' then?

I think what danf is saying is to leave out the demonstrative pronoun 'de'... is that right danf? but I don't think that's the intent, as these are 'books in Spanish FOR children' not books in Spanish BY children'... am I correct?

my 3 years of HS spanish are extremely faulty box but I believe your second example may be (more) correct.

damn I know so many good Spanish speakers, but none are at my office.

(los) libros españoles para niños.

The former means "for kids in Spanish," which makes me wonder how a kid got in Spanish. The latter makes more sense, but isn't the way I'd write it. But my Spanish is very rusty and wasn't really ever any good to begin with.

Indeed, these are books in Spanish FOR children.

libros para ni~nos en castellano.

at least here in chile (i asked a native speaker).

castellano? Is that the Chilean word for the kind of Spanish that people speak in Spain?

oh, sorry i never replied to this. "castellano" is what people call the language that they speak - what we call "spanish" in english. i have never received a completely consistent explanation, and i'm not sure if this is a way of speaking specific to s america, but once i was told that spain has more than one official language (basque must be another, i guess), and so there is no "spanish" language.

anyway, nobody i know would say "en espanol" (another possible reason is that s americans don't particularly like the spanish - seen as ex-imperialists - and so want to use a different name for their language...)

i don't think your explanation (the name for the language they speak in spain (as opposed to latin america)) is right - people seem to use it for the dialects of spanish (which don't differ that much - only a little more than american/british english) spoken here and in spain.