Deleted Disk Utility and Terminal!

So I recently had problems with an external hard drive, and was using disk utility a lot to try to fix the problem. Then, one day, I realized it was randomly gone from my computer. I could find it nowhere on my hard drive at all. Then a CD I put in my drive somehow got stuck (I think because it was damaged and not readable). I found online that it is possible to force eject a disc using terminal. So I went to open terminal, and it too is gone. I have not even used or seen that program for several months. I have no idea where these program went or how, but I would really like to recover them without having to reinstall my entire OS. Any suggested remedies?

A program called Pacifist can look at the install packages on your install disks and allow you to get back specific programs

Pacifist 2.5.2 software download - Mac OS X - VersionTracker

Thanks a lot. That got me back where I want to be.