Artcam is the most ridiculously overpriced software i have seen for many years. It is aimed at big business. yes its a fantastic program but unless you have a huge budget (or a pirated version)(who would do such a thing!!)
its way beyond the price range of us poor hobbyist. Aspire seems to have a lot of the functionality of art cam and even though it is still a hell of an investment seems worth the money. (a new version has recently been relesased but i do not know what improvements have been made.
if you want top build your own 3D models then 3D studio max is probably the best (in my opinion) out there and if you sign up for a "student" package it is 100% free.
Zbrush (or its free cousin)(forget what its called at the moment) is fantastic for adding detail to 3D models.
so get out there and google away (you never know what "free" software is available.)