From Joomla! Documentation
I think this page needs a prominant reference to some good books that help explain the architecture of Joomla I've been scrambling around in the dark for 9 months now and today I found Mark Dexter & Louis Landry authored book "Joomla Programming" I know it involves spending money, but, time is money too and I've spent 9 months scrambling around for scraps of info here there and everywhere
Several times I nearly abandoned Joomla because of the difficulty finding a solid reliable source describing the product architecture I'm not new to programming at all but Joomla is a big load of code, hoping my struggle eases now, so far so good, but only a few chapters in
I suggest authoritative reference texts should be referenced prominantly on the developers documentation homepage People can then go with the free info if they want but when they come back here, worn out from looking days or weeks later, they should find the reference texts.