Textbooks

There are only two semi-official textbooks are out there for the IB Computer Science 2014 syllabus and no officially supported/recommended IBO Computer Science textbooks. They are good resources, but perhaps a bit too technical for mid-range students and go into more depth than the curriculum explicitly requires.

Core Computer Science (that deals with the core syllabus, both SL and HL)
https://www.expresspublishing.co.uk/assets/microsites/corecomputerscience/

Advanced Computer Science (that deals with the extra sections for the HL syllabus)
https://www.expresspublishing.co.uk/assets/microsites/adv/#