Hi Sankar,
If you want to get a list of SAP institute, it is very simple to get it from
net but if you want to get legitimate one it is bit of difficult.
Substantially I would not suggest you to do SAP authorized centers
because of the cost involved and those institute will deliver their course
in 20 days.No institute can ensure placement since placement simply based
on one's ability to market him/her self with perspective employer.
Regards
Shereef