This will make you to an expert on using the Nikon D90, but this alone won't get great pictures. To get great photos you still need to get yourself to the right place and point the camera in the right direction at the right time, which is a lot harder than mastering the D90. Technically, lighting and the use or disuse of flash is far more important to artistic synthesis than your choice of camera.
Using the D90 is super easy once you know now. The settings can be tricky. Every time you go to use your Nikon D90, it should be super quick. no stuffing around. Get the menus right at the start. The light settings are important. Nikon DSLR is one of the best around. Discount cameras and information packs. www.nikond90camera.easychristmasgifts.org/ It does everything (even makes a cup of coffee ! - not really). I love navigating the menus, it is fun and you get to see how it all works.