SNARKINESS ALERT: You wouldn't need a waiver anyway even if you WERE flying in class e airspace.
However, you would need AUTHORIZATION. A waiver is for OTHER rules than airspace, such as flying over people, or flying at night, or something along those lines.
But entering controlled airspace requires authorization, which, from what I have read, is handled by a different department / different process than requests for a waiver.
END SNARKINESS.
And, yes, you are correct. If the area you are in has a shaded magenta border on the sectional chart, it is Class G airspace from the surface up to just below 700' AGL. And in those situations, you do not need authorization first.