In one of the tutorials Goop was recommended. I can't find that tutorial right now, but it's not in "Stamp Carving 101".

Does anyone know how Goop holds up because my stamps haven't had a winter yet.

You can find sheets of thick foam at Joann fabrics and sometimes at some Michaels. Then you can skip the door knocker thingys. I also slash the back of the stamp like Freddy Krueger so the glue can penetrate; makes a firmer hold.