Some of My Favorite Fantasy Authors

In no particular order:

Terry Pratchett (over 30 books, very funny, satirical, wonderful)
Jasper Fforde (Tuesday Next series, Nursery Crime series)
Neil Gaiman (you probably already read his work, Neverwhere & American Gods are favs)
Garth Nix (in particular, The Abhorsen series & Keys to the Kingdom series)
Charles DeLint (Into the Green, The Blue Girl, any of them really)
Kim Harrison (start at the beginning and give her a chance)
Tanya Huff (her occult series)
Holly Black (Tithe, Valiant, Ironside)
Kelley Armstrong (Women of the Other World series)
Lilith Saint Crow (anything she writes is good)
Melissa Marr (Wicked Lovely, Ink Exchange)
Tamora Pierce (anything she writes)
Laurell K Hamilton (anything she writes)
Jaqueline Carey (Kushiel's Trilogies)
Simon Green (Dark Side series)
Jim Butcher (Dresden Files)

People ask. So there it is. Searchable, even. ;)