I think Barbara Heidenreich is the best trainer who's writing about her techniques. Here's a link to 2 of her books that Amazon.com has discounted:
http://www.amazon.com/s/ref=nb_ss_b_4_1 ... barbara+he
(Edit: I see that the URL software is still malfunctioning. Just go to Amazon.com and search books by Barbara Heidenreich to find these two.)
She's the editor of
Good Bird magazine, which you might find helpful.
I still think it's a bad idea for you to bring a bird home, Lexii, especially a quaker, who'll need a LOT of your attention for the next 25+ years. At 14, you're on the cusp of an extraordinarily busy time in your life. I fear a parrot will interest you for 6 months, maybe 18 months if he's very lucky, and then he'll sit abandoned the rest of his life. This would be cruel, and I most fervently hope you don't let it happen.
I've spent over $1,500 in the last 2 weeks trying to save one of my birds. I'll bury him this weekend, if it quits raining. As I've told you before, parrots are very expensive pets. Please give this a lot more thought.