The Adobe Lightroom YouTube Channel has been the most useful resource for me. It’s easy to search for videos addressing certain topics, and the collection of tutorials is extensive.
While it is long, I found the following YouTube video by Terri White to be the most helpful and straightforward to getting started with Lightroom. I watched it in one window while following his directions with Lightroom in another window. Some of the topics he covered were not relevant to me, so I just skipped them. Generally though it was a thorough walk through for Lightroom.
I will say, there is quite a learning curve to really be able to take advantage of Lightroom. Basic photo editing features are quite intuitive, but things like presets (at least for me) take a bit more time. I am a big fan of the options for easily importing, naming and organizing photos.