I've been asked to make a "dummy" cake for display and donate a cake gift certificate for an art auction benefiting our public school. I want it to be a 3 tier stacked cake covered in fondant. I have never done a "dummy" cake before and don't know were to begin. Please Help!!! It is due THIS FRIDAY !!! Thanks!!!
Since it is due this friday I don't think you'll have enough time to order cake dummies. You may be able to find them locally, but they won't be at michaels or hobby lobby.
Here are a couple of alternatives.
1) Rice krispies - these are a personnal favorite b/c they are cheap and take me no time at all to prep. Then after displayed for a few days they are still good so just cut into them! Buttercream covered rice krispies are now a favorite in my family. For reference the yellow present cake in my photos is rice krispies and you can't tell. I just used the icer tip to put on buttercream and it was a nice thick layer so I could still smooth and not see Rice Krispies.
2) Head to your local home improvement store or hardware store that carries the 2" pink insulation foam. It is soft enough to cut (if you have the right tools) and the right height for cake layers too.
HTH
For your future reference. 
Covering cake dummies in fondant:
http://forum.cakecentral.com/cake-decorating-ftopict-172651-.html
The above multi-linked thread also has info on where to order for best selection.
HTH
I got my cake dummies from "fake cakes". VERY AFFORDABLE:
http://www.sugarcraft.com/catalog/wedding/Wfakecakes.htm
i just covered them in press and seal and misted them with a spray bottle for the fondant to stick. Easy, easy, easy. let me know if you run into problems.
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