One can find a guide for low resolution spectroscopy
This guide presents the various topics on which amateurs can work in low resolution.
Most of them relate to variable stars : Miras, Cataclysmics, Symbiotics, Novae ...
Hoping that it may contribute to the development of amateur spectroscopy.
French :
http://www.astronomie-amateur.fr/Documents%20Spectro/SpectroscopieBasseResolution.pdf
English (translate by Robin Leadbeater)
http://www.astronomie-amateur.fr/Documents%20Spectro/SpectroscopieBasseResolution_En.pdf
An italian version is coming
François Teyssier