Walter Hogan has written a book about Pinkwater called The Agony and the Eggplant: Daniel Pinkwater's Heroic Struggles in the Name of YA Literature.

Pinkwater is very prolific, having written over 80 books, including, but not limited to:

The Magic Pretzel (2000)
Ice Cream Larry (1999)
Attile the Pun: A Magic Moscow Story (1994)
Borgel (1990)
The Frankenbagel Monster (1986)
The Snarkout Boys and the Avocado of Death (1982)
Alan Mendelsohn, the Boy from Mars (1979)
Yobgorgle: Mystery Monster of Lake Ontario (1979)
The Last Guru (1978)
The Hoboken Chicken Emergency (1977)
Fat Men From Space (1977)
Lizard Music (1976)
Blue Moose (1975)

The best way to get a good introduction to Pinkwater is to pick up a couple of his "greatest hits" books. One of these books is 5 Novels which includes:

The other book, 4 Fantastic Novels, just came out in 2000, and includes:

Thanks to General Wesc for the extra info!