i'd be suggesting a macro as suggested before, for a few reasons. mostly b/c macro lens is designed to have a flat focal field, therefore for macro pictures and reproductive work u get a better image.
i have the canon EF-S 60mm f/2.8 Macro, and it is a great lens for the money. Once again, by the time you buy a basic DSLR, and get some lighting, and a lens that won't let you down, you are looking at 8-10k.
some point and shoots and a few pro-sumer cameras will do ok, but you really cannot beat a lens that is made for a purpose. any multipurpose product will have compromises (eg a pocket camera has amazing lens distortion, but great depth of field, is small, cheaper etc... a DSLR costs more, but a good macro lens will have negligible barrel distortion, and u can control the depth of field)..
the camera body is not really a big deal for what you want.
there are some decent third party macro lenses too. for a DSLR, 60-70mm macro is quite verstile, similar to the ever popular 100mm length on film/rull-frame cameras.
i think they make this for nikon too... it gets a highly recommended by photozone, FWIW