The Myth series by Robert Lynn Asprin. A complete rip-off and farce of science fiction and fantasy novels, and an absolute riot to read. The story is told by Skeeve, a very naive human from the Dimention Klahd and tells of his adventures with his partner Aahz, a Pervect from Perv, the brother and sister act of Chumley and Tanada, a troll and a trollop (both green in colour) and Skeeve's dragon Gleep. . .
The James Herriot collected works, beginning with All Creatures Great and Small.
The Xanth "Trilogy" by Piers Anthony - a whole series based around mostly puns. I think there are aroud 20 books in the trilogy now. The first book is A Spell for Chameleon.