Freelance VFX Artist Saber Jlassi has a nice tutorial series that shows how to model procedurally using, of course Side FX Houdini. Jlassi walks through creating a typical hard surface model (a computer fan), working with procedural methods. Moving from more traditional modeling methods to a procedurally based workflow can take some getting used to. You are basically moving from choosing and working with tools and exchanging those for nodes that are built for specific tasks.
If you have not yet seen how procedurally modeling something takes shape, you should, because it is a pretty impressive thing to watch. Similar to 3ds’s “modifier” stack, stringing individual nodes to create a larger network is an amazingly flexible way to work. Procedural modeling can very much be akin to an open field: wide spaces and fresh air. It will just take some getting used to. This Houdini modeling tutorial is a great start!