I spent a few hours putting together a step by step guide to drawing mermaids. I did this for the Mermaids Group on deviantArt. Mermaids have become more popular than ever--there's even a "World Mermaid Awards" con in Las Vegas next month.
I did all the art on the iPad in the Brushes app, using the Pogo stylus. One of the cool features of Brushes is the ability to generate a video of every pen and brush stroke, so you can show off any painting from beginning to end. I posted the video on Youtube here.
Here's the finished piece (warning: breasts)
Here's the video generated by the Brushes app:
Here's the Step-by-Step tutorial--click for the full view (very long)