I would recommend Recovery using TestDisk.
Boot Ubuntu from Live USB drive or CD, , run
sudo apt-get install testdisk
TestDisk is used to recover missing partitions and repair a corrupted one. It served me well in recent past to recover entire Hard disk , so i am suggesting it.
After installing ,open Terminal and run
sudo testdisk to get this
create to create new log file ,select the Hard disk you want to recover ,
Proceed upon selecting the Disk
Then select the
Intel option ,
Enter to proceed further.
Analyse to search for Lost Partition
Then it will list the Current Partition Structure , select the
Quick search option to list the
Deleted partition .
If Found Nothing then select the
Deeper search option to list the deleted partitions. It will probably list all the partitions created since the Disk was First used. You have to be extremely careful here.
For more in-depth instructions refer this Step-By-Step guide .If found proper listing of partitions , select the
Write option and Reboot to see the changes. Best of Luck .
Also refer below options before trying this above , here
How to recover deleted files?
Mitch's answer here for RAW data recovery
Ubuntu help page on Data Recovery