Led education frustration

[weyburnt]

So I'm trying to learn about what is availiable, an required for led lighting. I'm usually really good at researching and understanding, things. However I find there is alot of junk trying to sell crap regarding this topic. What are the best links to learn about things such as, required watts, lumens, controllers , lenses, LEDs, etc. As well I would probably want to go DIY ( as I'm pretty good with that stuff). Were are the best sources for these parts.