Tyler Hutchison, Applications Engineer
LTspice IV (http://www.linear.com/ltspice) can perform frequency domain noise analysis which takes into account shot, thermal and flicker (1/f) noise. The resulting noise density (in units of volts per square root hertz) can then be plotted to aid in circuit analysis and understanding.
This video covers how to setup a .noise simulation in LTspice to view both input and output referred voltage noise and discusses a couple of tricks to learn more about noise contributors.