Dzurlord - A Crossroads Adventure in the World of Steven Brust's Jhereg: 1987, ISBN: 0-812-56410-3
Not part of the canon, Dzurlord is really only notable for the introduction written by Steven Brust (which Brust later noted as substantially accurate). The rest of the text is not his direct work. This book is out of print but you can read the intro here. Used copies can sometimes be found on Amazon and other resale site.