hi. i want learn mechanical desktop2006 .who can help me?

Answer 1

I suppose you are referring to AutoCad 200x.
It is a VERY complex program: I have used it since mid eighties... and still learning.
Your best bet is to find someone who works with it (architect or engineer), and ask him to teach you a particular project (ie design an object you want to design). This will teach you some basics. After that, work your way through.
There are, also, courses offered by some universities as well as Autodesk (the creators of AutoCad), but these are payable.
It is, in my opinion, one of the most powerful programs on the market.
Good luck!