Let's see:
Piers Anthony's Magic of Xanth series. The first one is A Spell for
Chameleon. Here's a review:
Amazon.com
Though already developing a successful career in SF with such heady
novels as Chthon and Omnivore, Piers Anthony did not reach brand-name
status until he cooked up some fantasy in 1977. And it was cheerful,
humorous fantasy at that, as in his first Xanth series novel, A Spell
for Chameleon. The book's young hero, Bink, is without magical powers in