I've said it directly to ((ewe))yn, the video tutorials are GREAT.
And if' you have been a 'sloppy' (or 'hack') Joomla coder like I have gotten to be, those tutorials (and reviewing code directly) are great ways to 'clean up' your coding and using Joomla standards.
AND if you're not exactly sure how to implement a specific feature manually in code, you can build it with JCB and then go look at the code. That is a GREAT learning tool for anyone just getting started with Joomla (but experienced with PHP and javascript).
JUST BE AWARE ... when you get started you should set-aside a good deal of time to get to learn the system ... even just going through the videos will take 50+ hours at last count. So take your time and go through those and you'll be cranking out custom components in a LOT less time.