Programming an automata using context free grammar

Hi, I m looking for programming an automata that must remove empty derivaions from a text chain given, I would like to know if anoyone has programmed this that would give me a hint on how does this is done, or a good internet link about programming this steps,
-removing ambiguity
-removing recursion
-removing emty derivations
-removing unitary productions
-passing to chomskey form


I really would like something like an internet site with examples about how to program it, I am thinking about a recursive function, however, I am a bit lost

Thanx for your time

Well, I guess I'll kick off the discussion with asking what you've done so far. It's how we operate here.