GMs who like my Dying Earth Dungeon Starter:
(https://drive.google.com/file/d/0B7cav44145d9OUdDYnBKck9fWG8/view?usp=sharing) might be interested in the Vancomancer, a "Dying Earth" style wizard playbook for Dungeon World. (http://www.drivethrurpg.com/product/125796/The-Vancomancer-A-Dungeon-World-Playbook?filters=0_2130_44819_0_0 )
DCC's The 998th Conclave of Wizards (http://www.drivethrurpg.com/product/169644/Dungeon-Crawl-Classics-88-The-998th-Conclave-of-Wizards) seems very Vance inspired to me.
Pelgrane Press has a RPG full RPG devoted to this world with multiple supplements although the line seems currently inactive. (http://www.drivethrurpg.com/product/11946/The-Dying-Earth-RPG?term=dying+earth&test_epoch=0&it=1)