I would like to recommend the videocopilot link, It's a very cool After Effects Tutorial, and if you purchase their evolution package you get cool flourishes that grow out, then you can modify them from there, which is simple, and generates something pretty cool. The tutorials are really 10/10 so even a beginner should be able to do it.
But if you were talking about a program to make your own flourishes from the beginning? If you need them for a banner or something, than www.deviantart.com holds many free flourishes, that is easy to edit in photoshop, and if you wish to make them "alive" than you can apply a mask layer and move it along with the timeline.