The first book I ever read of Neil Gaiman's was Good Omens, the one he cowrote with Terry Pratchett. My feelings pretty much mirrored Nathan's. I'm a big fan of Pratchett, and after reading Anansi Boys, I'm guessing that Good Omens' shortcomings were a case of too many cooks in the word processor, because Anansi tops it in every way.
The protagonist is Fat Charlie, who is not particularly fat. He is leading a relatively normal, boring life, engaged to a girl who doesn't seem to like him much, stuck in a job under a weaselly boss, and basically spending life in as average a way as possible. However, things are about to change.
Charlie's father dies, and, surprise, he learns that he has a brother and that his father was the god Anansi, a sort of Loki for the Indian set. Hijinks ensue.
This book is very funny and well-plotted, and worth reading if you like light fantasy. And this review sucks. It is not recommended to anyone.