Creating a Vase in ZBrush

Use the radial symmetry to construct the overall shape, mesh extraction to cut the hole and finally use the ZProject brush

http://www.cgarena.com/freestuff/tutorials/zbrush/pixozbrush/vase.html

ZBrush: Getting Started 28 Videos

These 28 video tutorials will help you in understanding the interface and tools inside ZBrush and getting started

http://www.cgarena.com/freestuff/tutorials/zbrush/pixozbrush/index.html

Video: Learn Sculpting in ZBrush - Part 4

In this fourth part Jason Welsh talked about introduction and structure of Zsphere

http://www.cgarena.com/freestuff/tutorials/zbrush/sculpting_series/index_part4.html