I haven't tried building my own ROM, but XDA is my first (and usually only) stop when I want to flash a new one. Don't most developers make the code open source

I haven't tried building my own ROM, but XDA is my first (and usually only) stop when I want to flash a new one. Don't most developers make the code open source? Perhaps poking through others' code would clarify some things. I'd be willing to bet people hang out in some IRC rooms, too.