ashish.pbh wrote:unexpectedly i formatted the whole 500GB system(which constitutes 2 partitions).
What kind of format you have performed (I didn't play with Ubuntu for quite some time already)? Was it a quick format or a full one?
After a quick format data should be recoverable. Overwritten files are lost.
Also I'd suggest you to find a Windows machine, connect your drive to it and proceed there, as this way will give you the most options in terms of software.
If bootable recovery CD is the only way, then here's a specialized one:
http://www.ufsexplorer.com/recovery_cd.php(based on Ubuntu as well, BTW)