System Restore doesn't restore your own data files, it's only designed to restore system files, drivers, etc.
A deleted music file is like any other deleted file -- it still exists on the drive and can usually be recovered IF you have contained further writes to the drive. It's imperative in a situation like this where a file(s) are accidentally deleted that you [i682b030a56]immediately[/i682b030a56] shut down the system. Any further activity results in writes to the drive, which risks overwriting the areas that have been marked as available by the deletion, especially if your drive is more than half full. Just booting into the OS could generate enough write traffic to destroy many of the deleted files permanently.
Ideally you would pull that HDD and slave it to another PC (the easiest wasy is with a USB converter or enclosure), and run the undelete software from that PC. The next best option is to boot from a recovery CD that includes an undelete function. Something like Ultimate Boot CD[=http//www.ultimatebootcd.com]Ultimate Boot CD
which is a free, Linux-based bootable toolkit CD that has FAT/NTFS utilities. There is a Windows version, UBCD4Win[=http//www.ubcd4win.com]UBCD4Win
, that uses BartPE and Windows-based tools, however it requires you to build it from an installed Windows machine to get the necessary Windows system files it needs. If you have a second PC you might try that one and like it better.
Last resort, use another PC to download an undelete utility such as FreeUndelete[=http//officerecovery.com/freeundelete]FreeUndelete
to a USB flash drive. Boot your PC (realizing even this could risk some of the files), and run the undelete utility from the USB drive.
[b682b030a56]EDIT[/b682b030a56] Now that I look at it, Ultimate Boot CD (the original Linux version) might not have an NTFS file recovery tool. UBCD4Win has several (including the aforementioned FreeUndelete) so if you have access to a Windows PC to build it, that would be a good one to use.
Note if this is a Vista machine, proceed at your own risk. Vista changed some things with NTFS that can cause your system to not boot (or boot into Vista Recovery Mode) after running some file system tools that aren't Vista aware.