An affordable source of good ebooks is 
Craft & Vision. They offer PDF format books at very reasonable prices and I have purchased quite a few from them. They make for interesting reading and looking at different photographs. They are running a sale TODAY ONLY on some of the collections at 50% off with special discount codes. I received their announcement in the mail, some of you might have gotten your own copies. For the benefit of those who may not be on their mailing list, I am sharing a link to the discount announcing e-mail. I have purchased two more book just now, both for $4! And you can instantly download the PDF books. Take a look, well worth the money.
