We specialise in Joomla and I have to say the only annoying thing is it loads the odd table for layout, but when you have it down its so easy.
It can be limited and depending on your knowledge some things can be really long winded but for the average Joe its good tbh.
Haven't used wordpress so can't answer that bit of your question, but learning on-line is how I learnt. I got a book and it was utterly useless I really struggled with it, swapped to on-line resources and I flew though it so quickly.
If you need any help give me a shout/start a thread and I'll help you out.