CAP 459 Civil Aircraft Inspection Procedures is a very informative document, but has been superseded by CAP 562 Civil Aircraft Airworthiness Information and Procedures, which in my opinion is not as good. CAP 459 is no longer available/amended and as such is not an approved publication, but see below.
CAP 562 is available from the CAA via Documedia. This is the publication you should be able to get hold of, it is amended and contains all of the up to date info. Unfortunately most of the really obscure stuff in CAP 459 is missing.
Documedia info
CAP 562 link
As for the original CAIP If you visit
Here you can get access to this document online. This is the aircraft engineers website you will need to join the JAR66 Club. Details on the site.
Hope this helps.
Regards
The Doc