Re: Photographers???
the manual is the foundation. if don’t know much about your camera or photography, it’s a goldmine of information.
not only will it tell you all the functions and settings within your camera but it will teach you about exposure - setting aperture, shutter speed… how to compose photos… etc etc etc.
http://www.paklinks.com/gs/rangon-ka-shajar/323468-photography-dummies.html
i too have a D90, 4 lenses and a speedflash, so far.