If you have a AC Moore or a Micheal's near you....in the cake decorating section there is a dry mix called whipped cream frosting, I know that Wilton brand makes one that is the same thing most commercial bakerys use. If you want to try your hand at your own, hear is an easy recipie.
Whipped Cream Frosting
2 cups heavy cream
1 cup powdered sugar
1 teaspoon vanilla extract
1 packet (2 tablespoons) powdered gelatin (knox or other brand in the pudding/jello section of your supermarket)
1/4 cup cold water
Before making frosting chill a stainless steel or glass bowl for thirty minutes in the freezer, make sure heavy cream is cold, straight from the fridge. Put water in a small bowl and sprinkle gelatin on top to soften gelatin. Put heavy cream, softened gelatin, and vanilla in cold mixing bowl and start beating on low of stand up mixer or with hand held electric beaters, until slightly frothy, add powdered sugar a 1/4 cup at a time while still beating on low, then increase speed of mixer to high and beat until whipped cream consistency. This doesn't have alot of the stabilizers and chemicals that commercial frostings do, so it is best used the same day it is made. Good Luck!!