weaveworld and imajica were always my favorites, but the great and secret show/everville have some really fond memories attached. i love clive barker, always have. i kind of forgot about him for a while, and anyone who loves neil gaiman should check clive out just to see how much gaiman was inspired by/ripped off barker. (*cough*coraline*cough*).

i couldn't get into much of the abarat series or mister b. gone, but really everything else is amazing.
@Maul - start with the first three volumes of the books of blood, generally bound together. "in the hills, the cities" is one of my favorite short stories of all time, and "dread" is no slouch, either. you might recognize a pivotal line lifted from the text of "in the hills..." in a certain track seven from a certain 1989 debut.