Does anyone have any suggestions for dressing up buttercream? I need to make some accents sparkly or pearlized but have never attempted to do this with buttercream. Any help or suggestions would be appreciated!!!

You can certainly airbrush buttercream with pearl dust. I have also brushed well-crusted buttercream (cornelli lace, specifically) with gold, silver, and pearl dusts mixed with lemon extract. You just have to have a gentle touch so as not to dent the buttercream.

Making fondant accents pearlized and sparkly is much easier if you don't have an airbrush for the buttercream. I'm sure others will have other great suggestions, though.