Hi Michelle,
I know the one you mean - it was one made by Cuttlebug but has now been discontinued. 7 Kids College Fund had some but I just checked and they are sold out. I did find one on EBay USA
here which is up for auction.
As an alternative: Sizzix have a set of 2 embossing folders called Spiders and Spiderweb -
here is a link to the set at CropStop. Plus they have another one by Sizzix called: Halloween - see
here. Simon Says Stamp also have both these sets. Simon Says Stamp also have a
Hero Arts Cling Spider Web stamp - maybe this could be an alternative (?)
Hope this helps a little...... ;) Jocelyn