I just finished up another free subdivision surface modeling video.
Modeling a compound curve cutout on a subdivion (subd / subpatch) object -
In this video tutorial, I show how to cut out a curved object out of another curved subdivision object. In this specific example it shows a flattened cylinder being cut out of another cylinder. There are no extra plugins required for this tutorial. Although this tutorial was created in Lightwave would work in any modeling application (Max, Maya, C4D, Softimage, Wings3d, Silo, etc) that has subdivision surfaces and allows either vector moves or point slides. The video tutorial also shows an easy way to cap off the ends of a 24 sided cylinder in quads only.
Modeling a compound curve cutout on a subdivion (subd / subpatch) object
My other subdivision/subpatch videos
I hope it helps out! Enjoy!