A quick reaction to a few of the ANH eBook goodies:
One really cool video shows the original version of the title card. Originally the STAR WARS logo (in a different design) didn't recede straight backward. Instead it started out in normal orientation, then folded over backwards into the plane of the opening crawl, and then receded, followed immediately by the crawl text.
We also get concept art by Ralph McQuarrie and John Mollo for Princess Leia; McQuarrie draws Leia as a blonde, and Mollo gives her light brown hair. (Mollo recalls that Lucas at that point wanted Leia to resemble Jean Harlow.) In fact, there's a new photo of Carrie Fisher trying on a dark blonde wig.
Mollo consistently draws Luke with blond hair--sometimes short like Flash Gordon's, and sometimes longer like Mark Hamill's. Which helps explain why Hamill got the part.
(Frankly, Hamill had the WASPy, blond, Flash Gordon look that Lucas wanted for his hero. On the other hand, Will Seltzer, who was the front-runner for the Luke role until Hamill auditioned late in the casting process, had curly brown hair and was ethnically Jewish. The fourth-draft script of ANH, written during the time of early casting sessions, describes Luke as having Seltzer's "curly hair," but the revised fourth-draft script changes it to Hamill's "shaggy hair." In the third draft Luke had "short hair.")
Oh, and Rinzler has unearthed a previously unknown rough painting by McQuarrie, of a scene that occurs in the rough draft and the second-draft script of ANH. It shows Annikin/Luke Starkiller stuck high in the treetops of Yavin, having just crashed an escape pod, and about to deal with a monstrous spiderish creature perched on his chest, looking for a meal.