Measuring red shift

Fairly frequently our astronomy club secretary who is also the Presidential award winning high school physics teacher brings the physics students out to my large Dob for a session of stargazing. I have been wondering what equipment would be necessary to actually measure redshift of objects. The large Dob is not a driven scope but I have other scopes that can be equatorially mounted and are capable of imaging. I think I heard that SBIG had some type of spectroscope for "us amateurs." Is it beyond reason to try to assemble the equipment for amateurs to attempt to measure red shift for purpose of education of students about how this information is actually obtained? How bright would an object have to be for one to gather enough light to create a spectrogram that would allow doing this? I am an absolute neophyte on this subject--armed with a spectrogram how does one know what the wavelengths are to know how much shift has occurred? I'm hoping that Maurice and some of the other physicists out there will weigh in on this one.