I'm am and still tying to learn as much as i can. I stumbled upon this really good informative site with videos. Of course some if the site one has to pay for but there are a good bit of videos that are free.
I like the site and the youtube videos, but when i posted some of his info on here a couple of years ago, the self appointed diesel expert on this site led me to believe that he is nothing but a hack and slammed him kinda.... I think the guy is very helpful and knowlegable.