A good friend, a professional photographer uses the Nikon D100.
He used to use a Fujifilm FinePix S2 but converted due to Fujifilm's huge appetite for battery power.
He gets most of his supplies from
B&H Photo . B&H has a lot of high quality used equipment. New users, keep in mind most top of the line SLR's don't come with lenses.
Hope this helps.
Niko