Macro lens for Nikon D90?

I want to take shots as close as a watch dial. I don't want to take shots where i can see the hair on a mosqito's legs. What whould be the best lens for me? I have seen the Nikon AF-S DX 40mm f2.8G but not sure if that is the right one as i don't have experience in macro lenses. My 18-200 kit lens just does not do the trick.

Best site now on the net is this one. HD too!