i am making some buttercream "dummy" cakes for display, is there a particular buttercream recipe that is best for this, cuz it will be sitting out for a long time to come! are there certain ingredients to stear clear of? tiz

The Wilton class buttercream is perfect for dummies:

1 cup vegetable shortening
1 lb powdered sugar
3-4 tbs. water

Yes, what she said....If you want a softer/creamier icing to work with increase the shortening until you are satisfied with the consistency.