How can I turn off the message "this message was sent via a blackberry" when I send an email? I checked the Autosignature and it is blank. and I don't see an option to turn it off on my BB

Go to your VZW BIS website, and edit it there.

Where can I log into my BIS account? - BlackBerryFAQ

I am on a BES does that make a Diff? And where would the setting be? Sorry for my ignorance.

click on messages icon on device. scroll up to the top (so no message is selected)
click side-wheel for menu
click on options
click on email settings

your "use auto-signature" should be set to yes, and you can scroll down to that field and edit what's there.