Just to be sure we're using the same terms, I've attached a picture. As a pad for the jack itself (main pic) I recommend a hockey puck. If need be, you can easily cut it down to fit the cup on your jack (mine fits under the car without needing to be trimmed, but if you've got a lowered suspension...). An alternative is
here. Jack stand pads can be had from a lot of places, the inset picture is from
http://www.protechproducts.net/jackstandpads.htm for instance. Google search came up with more references than you could ever need. Another alternative commonly used is a block of wood on top of the jackstand.
BTW, I use ramps instead when I do the oil change. Way simpler in my opinion. I just back up onto the ramps (raising the rear of the car) and roll under with the creeper and drain pan, etc.