Totally lost for which, and how many, fans I should get from Canada Computers.

There are two types of computer fan; AF (air flow) and SP (static pressure). AF is designed to move as much air as possible and SP is designed to move air through tight spaces. AF is used for case fans and SP is used for CPU heatsinks and AIO radiators. Fans that move more air are generally louder, as you'd expect.

In terms of layout, this is the usual approach:

Front - intake
Side - intake
Bottom - intake
Rear - exhaust
Top - exhaust