Well, getting started in the Nikon digital world could take you a couple of different ways....
Right now, a lot of folks are selling their D100's in anticipation of upgrading to the newly released D200. Prices seem to be anywhere from $500-700 for a good D100. With that, you get a 6 megapixel body that's been extremely reliable. You can, of course, plug in just about any Nikon glass except, I think, non-AI'ed stuff, and keep the automation for exposure. The body has the ability to turn off the autofocus, so you've got that option regardless of whether you're shooting a manual lens or not (I normally keep AF off when I'm working in the studio, anyway).
Maybe you could arrange to rent one or borrow one to see if it'd do what you want.
You could, of course, jump in with both feet and go the D200 route - a 10.5 MP body, for about $1700 (if you can find one, yet), but I'm guessing that's probably not what you'd want to do (anyone shooting with an FM2 probably isn't sold exclusively on the glitz and glamour of a shiny new body) (Hey, I've still got, though haven't used in a few years, my F3HP so I can relate! [img]/ubbthreads/images/graemlins/wink.gif[/img] ).
That help any?
This is Jennifer