Q:

Windows 7 to Ubuntu - erased data

I am quite new with Ubuntu and I am not that good with computers at all. I had Windows 7, however due to some problems I didn't like that operational system because of that I decided to install Ubuntu.
My problem is: before installing Ubuntu via USB drive, it gives a chance to the program to be tested through it. However, by mistake, I started the installation of the operational system without giving any directory. As you all know Windows has two partitions "C" - where the system is written and "D" - the hard driver. By begging the installation my entire information and the drivers "C" and "D" were deleted. Furthermore  at the moment instead of showing "C" and "D" it shows up one partition with the entire memory of the computer.
At that point by stopping the installation of Ubuntu, the computer does not have any operational system only the BIOS (which i am not quite sure what it is). Furthermore the computer is running at the moment by using the Ubuntu operational system installed on the USB. Since it happen me that accident there was nothing over-saved on the computer. 
My question is: Could it be restored the partition "D" (as a partition) or at least the data within that partition?
If you are going to ask me did I made a backup on some external hard, the answer is "no". Because of that please if some one knows how to restore the lost data to help me. I do believe is still possible to be saved. If you have any further questions please do not hesitate to ask.

A:

If the documents and pictures you want to recover are important to you, take it to an expert.  Would you forgive yourself if through an accident or improper action taken when trying to restore, you were not able to restore everything, or you accidentally lost the lot?
An expert will be able to restore more than most tools.
If you don't, then I can only advise, do not do anything more that will write to the drive.  Do not try to install an operating system on it or boot from it.  Boot only from rescue CDs or the Ubuntu thumb drive.  Buy a second drive, bigger than the one you want to restore from.  When restoring, restore to the extra drive, not touching the original.  Testdisk/photorec are decent restore programs but quite technical and recommended for experts, especially when doing an accidental format restore, which is what this is.  You'll want to search for lost NTFS partitions with cluster size of probably 4096 (4kB) and recover from them.
I'll also say that your chance for being able to restore most of your data is very good, especially for (what used to be) the second partition (D:, I assume).

