Although not specifically focussing on procedural content generation, these short and fast video tutorials can be helpful for beginners and a great source of inspiration for advanced Houdini users alike.
The Youtube channel of CG wiki discord by Matt Estella shows lots of fast tricks and setups for SideFX Houdini by various discord users.
https://www.youtube.com/channel/UCGtGQa7AsDU00v0ntey_S9g
Pixel Fondue's Floyd presents dozens of quick tips for using Houdini. Look at the time!
https://www.youtube.com/watch?v=Gz9bUR0Vbe8&list=PLv8HciXoFYX8xGBC8ufmNamFdUMT0fhHf
Paul Esteves Twitter and Youtube accounts feature lots of quick videos on how to setup many procedures in Houdini.
https://twitter.com/PaulEsteves28
https://www.youtube.com/shorts/1V4R8gcy24Q