Well the main thing with the alto is that if you are buying brand new you have to be on a waiting list for more than 4-5 months. Therfore unregistered and newly registered cars actually tend to be more expensive as some people buy cars waiting on the list and sell them brand new for business. This is what has caused the confusion in pricing. One of my friends bought one newly registered for 15.50 when the A*W price was only 14.75 since he had an urgent need and couldn't wait.
But overall I would advice you to hold on till the prices settle, things are still shakey and unsure since the budget seems to be swinging back and fourth.
The Stig's post in How To Negotiate On Used Car Price was marked as the answer