Also you may want to try the NMRA website tons information (beginner to advanced).
http://www.nmra.org/
Benchwork you can look at this website open grid may be the easiest
to start with. I agree with the other post that you may want to investgate
different scales (small -like N scale or large Ho or G scale huge).
I think N scale is an interesting scale to start out with and he can learn from there, HO there is much more available though.