This two part tutorial for Sony Vegas explains how to use 3D (axis' X Y Z). It will tell you the fundamentals to work in 3D space, and also give examples of using this.
Difficulty: Moderate to Hard
Prior Knowledge: Masking, Basic Video Effects, Basic Track Motion, Layers and Tracks.
This tutorial was taught using Sony Vegas 7.0d. It will work from versions 5 to 8. You do not need PRO for this effect to work.