• irder book,
• krder book,
• lrder book,
• prder book,
• 0rder book,
• 9rder book,
• oeder book,
• odder book,
• ofder book,
• otder book,
• o5der book,
• o4der book,
• orser book,
• orxer book,
• orcer book,
• orfer book,
• orrer book,
• oreer book,
• ordwr book,
• ordsr book

The adjective form of the word "order book" is "ordered"

The plural of the "order book" can be the "order books".

The singular of the "order book" can be the "order book".