@mithun, in India you get Dynamat, Dynamat Extreme, Fonomat, WURTH, Pylemat and a few other names I don't remember. These are usually available with most good installers.
Fonomat cost approx. 250/- per sheet. WURTH is a bit lesser. Not much idea about the others.
More than the per-sheet cost, it usually takes about 5K to decently damp a hatchback's front doors, boot and C pillars. Doing the roof will cost a bit more.
__________________
Alpine 9887 | TRU Tech S44 | Image Dynamics XS65 | Image Dynamics IDQ12 D2V2 | Connection Audison |