widget and pulldown
Are you looking for the toggle that shows up on the notification pulldown or as a widget on your launcher?
If you're looking for one that shows up on the pulldown, you may be out of luck on a Samsung/Touchwiz rom, but most AOSP/CM based roms have a customization screen where you can pick exactly what toggles you want.
If you're looking for a widget to put on your launcher, there's a number of good ones that I've used. For just mobile data, "Data Enable Widget" by "FARPROC" is a good one, but for my Note2 running a Touchwiz based rom (which lacks a general "power" widget), I'm using "Powerful Control" (also by "FARPROC"). Both are available for free on the Android Market.
Best of luck.