Basically it's like alot of very small bends that you do very quickly up and down.

If you see tableture that looks like this
----------------
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---5~~~~~~~-
----------------
----------------
----------------


That means that you vibrate the string with your finger at the 3rd string 5th fret.

Hope it helps.
(Don't feel stupid, Hey, we all started at one time or another0

[This message has been edited by Luke (edited 08-16-2000).]