This tutorial was done in 3ds max 4 but the technique itself is usable across any 3D software that supports subdivisions / meshsmoothing. It assumes that your software also supports the selection and splitting of edgeloops and edgerings although traditional cutting will work too. It's just so damn much slower...

Knowledge about the following is expected:

- Subdivision surfaces
- Edgeloop and Edgerings
- Quad polygons

1)

We start off with an outline of the ear, created with a spline

The spline is then extruded into a solid shape

We now extrude another notch and bevel inwards

Next an edgeloop is added

We remove the large polygon inside and parts of the front. After some shifting of vertices we end up with a C shape

By extruding the one end several times we shape the rest of the inside  

Now we can close the hole again, making sure to end up with quads if possible.

Next we add some more rows of edges to the inside to create the ridge of the Antihelix. I just read that up so it has to be right.