What do Air Traffic Controllers (tower supervisors) say to pilots before takeoff and landing?
ICAO document 4444 contains phraseology and pronounciation in chapter 12. It might however be a little bit difficult (but not impossible) to find online, as ICAO documents are rarely officially published online.

CAP 413: Radiotelephony Manual is published by the Civil Aviation Authority (CAA) in Britain, but is considered reference material for pilot training throughout Europe. CAP 413 is largely built on ICAO doc 4444.

Phraseology in the US differs somewhat from ICAO standard (but is getting more and more harmonized). The Pilot/Controller Glossary published by the FAA may be of some help.