If you have deleted the entire Utilities folder and therefore all the programmes within it, things look rather serious.
The only solution that I'm sure would work is if you have your system backed up on Time Machine (TM). If so, it's a matter of entering TM, going back to a date before the accident, selecting Applications and then highlighting Utilities and "Restore".
But if you have not got TM, or indeed any backup, then I can't think of a way of recovering your loss. And the problem, unfortunately, is that there are several other useful/essential apps within Utilities which will be lost as well.
As far as I know, you can't download Utilities as a separate item from Apple. Do you have a TM backup?
Maybe some others could chime in with suggestions before considering a backup and clean re-install of your OS.
You can, IF you have a copy of your OS on a thumb drive, use a neat little Utility called Pacifist by CharlseSoft, and by Extracting JUST the Utilities Folder from the OS X Install ESD.pkge you could very well get it all back, w/out installing the OS again.
Sorry to say this; but I can almost guarantee that you will need Disk Utility again and quite possibly some of the other apps in Utilities. For example, Activity Monitor, Adobe, AppleScript, Bluetooth, Console, Terminal, Keychain access app, Migration Asst. Okay, maybe not all of these. Just saying that Utilities is well named!