Disk Fragmenter?

Does anyone know where I can download a fragmenter for my C drive? I ran a defragment this AM and everything has slowed down a little more. This appears to happen each time I defragment, what I think I need is a program that will scramble all of my data so that it will speed up.
Any help will be greatly appreciated.
Thankyou all.
Will
Any help will be greatly appreciated.
Thankyou all.
Will