I accidentally deleted my iPhone backup file from the backup folder.
Where are other places a backup could be stored for someone using Windows and iTunes?
You sould use some file recovery tools to recover deleted files. Operating system do not delete exact files. Only delete the file references. If you're lucky, OS do not replace your old file's partition with a new file; so you can recover.
iOS only backs up to iCloud and to iTunes, so unless you have another copy of that backup or another computer the device has synced to, you might be left with data recovery on the PC.
Is the iOS device still around to make a new backup?
in Windows 7, iTunes backup are stored in: \Users\USERNAME\AppData\Roaming\Apple Computer\MobileSync\Backup, unless you moved it or made a copy anywhere else. Using undelete software doesn't always work, as Windows starts to overwrite deleted files in time, to recycle space - if you do try to undelete, I suggest you stop using the partition it was on, to maximise your chance of finding something. Try the Reincubate Recover Files, it might help to recover your backup - it also has a deep scan mode for hard to recover files so try that as well. Hope it helps!