Kiesow is a German fantasy author, based on DSA not AD&D - but... <nervously looking around> he's... let me put it this way: I couldn't read him.
Quite interesting ones are Hohlbein, but just the ones he and his wife have really written for kids/youths. If he writes solo, he drifts into the Stephen King sector.
But I'm sure, you know Michael Ende, hm? The Neverending Story? NO, not the film, Steven Spielberg committed a major crime with that <img src="/ubbthreads/images/graemlins/memad.gif" alt="" /> (ruined the whole wonderfully composed plot with his stupid Disney effects) - or, Momo?