I couldn't find any inexpensive fake fruit but a couple packages of foam pumpkins and gourds from Dollar Tree was good enough. Then broke out the epsom salt and Mod Podge (any kind of glue would work).
I flattened out some Christmas ornament hooks and stuck them in the bottom of each gourd. You could also use a paper clip or any small piece of wire. Then just brush some glue all over it.
I sprinkled epsom salt all over them and stuck the other end of wire into a piece of styrafoam to let them dry. My son thought that part looked fun so he added some ornament hooks of his own.
Once dry, use the ornament hook to secure the "sugarplums" to your garland, wreath or tree.