This covers the basic equations for noise and more advanced analysis but it distills down most of the analysis into good rules of thumb.
The highlights include:
every 1K orf resistance adds 4nV/Hz noise.
noise adds as the sum of squares… so – larger sources dominate and large gain in the first stage minimizes noise contribution in later stages
Source impedance needs to be considered in terms of its effect on op map current noise( often ignored)