Possible Clues:

• Continent oddly not one seen in map collection!
• Place oddly not one found in map collection?
• Mythical island: Santa left it out!
• Titan carries books on island, a legendary one
• Archaeological adventure novel by David Gibbins
• Lost land from biblical books, one in mountain range
• Island not traced? It's given name, turning up in map book
• Shuttle that docked with 14-Down
• Lost city spelled out by the lost letters in the lower half of this puzzle
• Lost island silly nit recorded in map book