For fantasy, I suggest Tamora Pierce - too many books to list here, but her website is listed below. 'Song Of The Lioness' is the first complete series.
I also recommend 'The Unexpected Dragon': 'Pigs Don't Fly', 'Master of Many Treasures' and 'Dragonne's Eg' by Mary Brown.
'The Prydain Chronicles': The Book of Three, 'The Black Cauldron', 'The Castle of Llyr', 'Taran Wanderer' and 'The High King'