My recommendation would be to search YouTube for "Rick Hartley". The guy is extremely knowledgeable, yet humble, and presents things like grandpa reciting a war story. It's easy to listen to, and I'd take him being on any kind of program as an endorsement that it'll be high quality content.

The most important talk for beginners getting into high-speed is probably this one: https://www.youtube.com/watch?v=ySuUZEjARPY because without proper grounding, interference and EMI is going to destroy your HF signals (for example CPU to RAM bus).