Hi there folks! There's now a new tutorial series up on the Side Effects Software Inc. site called Introduction to Fluid Dynamics in Houdini. This crash course series focuses on the concept of fluid dynamics and how they work within Houdini. The free 2 hour 48 minute long collection of 15 Fluid Dynamics Tutorials contains both the basics on working with Voxels and working with Smoothed Particle Hydrodynamics that should help even the neophyte get up and running.
Enjoy!