Fantasy book about man who turns into dog/wolf and goes to a different dimension and fights evil overlord

Update: The book is Top Dog by Jerry Jay Carroll

When I was 14 or so (2005) my uncle bought me a paperback book I want to say had a dog paw print on the cover? It was about a man that turned into a dog or wolf and was transported to another dimension. He became friends with some other kind of animal and learned that there was like a dark overlord that was horrible. Things get spotty from there but I believe the ending he wakes up and is a lawyer or stockbroker.