As mentioned in another response:

The "Mastering Lightning" book by René, Laolu and Andreas is a good start. If you're more into web stuff, the plebnet wiki and the plebnet telegram group are a good point of entry as well.

Rene Pickhardt's videos on youtube are very informative as well.

As a lightning centered podcast, I can strongly recommend "The Kevin Rooke Show", you should give him a follow on twitter: https://twitter.com/kerooke