Mick,
I think you are on the right track. You will learn a lot and you can always upgrade bits and pieces later on.
Since you already have a D40, stick with that and save your money for other stuff.
You will need an IR remote control for the Nikon (ebay) and an illuminated reticle eyepiece in case you don't already have them. A spare battery for the camera (ebay) is also a good idea and a dust blower to keep the camera sensor clean.
Deal extreme has 'em.
James