1. Watch this illustration
Air-to-air heat pumps : central/distributed vs ductless, mini-split

(source : http://fr.slideshare.net/fortunatmueller/be-2014-heat-pump-and-pv – slides 33 to 37: Types of heat pumps)

Further information here (Energy Saver) : on air-source systems in general; on ductless, mini-split systems.

2. Lots of interesting information on Worcester-Bosch heat pumps website, e.g.
– Renewable technologies brochure, with descriptions of various types of systems
– Installation instructions and user instructions for air-to-air heat pumps
(downloadable here)
– a video showing the installation of an underfloor heating system (air-to-water)

3. On This Old House (a website devoted to home improvement), videos on
– how to position a mini-duct air conditioning system : all parts are shown very clearly.
– how to install a mini-split air conditioner

You can find many videos on YouTube showing the installation of heat pumps. Enter the name of a well-known manufacturer, such as Daikin, Sanyo, Honeywell, Trane…