Don't Worry, It'll All Be Fine
One thing I've learned as a GM with a handful of other GM's that have come from my group is the same thing I've learned as a teacher and educator: cognition builds skill.
When I try to help my players transition into becoming GM's of their own, mostly for the sake of not being the forever GM, I try to teach them to think about the process of actually running a game. Once that's done, we identify areas of concern and ways to work through them.
For your question, it sounds like the player in question has issues with paperwork. That's true for a lot of novices, and even some more advanced GM's, especially those with a focus more on storytelling than on mechanics.
My advice would be to help them find ways that work for them. There's any number of "spell card" style products where you can buy printed spells, and the reason for that is that they're a great tool for novices. While I'm not a fan of them personally, encourage the GM to write down things (or type them up if they use a device).
Also, I know this may be irritating, but the only way I've ever known novice GM's to start doing paperwork is after they've had some embarrassing mishap, myself included. Now, I use a tablet or laptop whenever I run a game (or, if I can't have that, a smartphone), so I tend to have a digital rulebook or a SRD and I've gotten pretty handy with CTRL-F, but people don't always have those skills. It comes with time and experience, and you might need to gently point out times when it would've been better to have stuff written down when you see lapses in bookkeeping.
With regards to books, I would encourage you to let him explore at his own pace. A core rulebook and some room to expand and explore works better than necessarily having a full library of rules and content. Likewise, although a novice may make system-related mistakes when first transitioning from playing in a game to running the game, and that's especially common when playing in a game that has a lot of front-loaded preparation (for instance, D&D, which has a focus on balance and power levels in 3.5 that can make it easy to accidentally smash a party of adventurers).
As a general rule, people will move on to new content when they are comfortable with what they know: if you're talking with the GM and they say "So, I'd like to include something like this..." you might want to say "Oh, the Book of Intellectual Property Neutral Stuff, Volume 8 has something like that.", but otherwise let the GM go at their own pace. For instance, I'm a speedreader and a former featured reviewer on DriveThruRPG: I can go through a game in a matter of hours, run through a few scenarios, and have a grasp of some ideas for how I'd run an adventure. Someone who isn't a speedreader, doesn't have a whole lot of experience with game systems, and doesn't have a whole lot of time might get through a book a month.
Just handing someone books doesn't make them better at a game, and while people who can use a ton of books can bring both setting elements and mechanics together in beautiful, optimal harmony, I've found that just handing a newbie more books (or, in this case, getting fifteen books when I grab a system, since I'm willing to confess) doesn't always make them a better GM.
One of the best ways to improve a GM is to be honest with them. Give them anecdotes from experience, suggestions for improvement, and identify the areas of concern with what you've seen. Do so in a way that isn't pushy:
"That encounter really stomped us into the ground! I remember back when
I was running a game, and I accidentally put a Tarrasque in with five
level 1 adventurers. The DMG has some advice on how to make encounters
that are a little less one-sided."
That's not exactly how I'd word it, but you get the general point: don't be like "Dude, that was awful, those trolls were five levels too high for us and we just got wrecked. Make the encounters easier!", because that's not helpful. I've done the unhelpful criticism with vague action step thing enough times to know that it just frustrates a new GM.
One thing to consider as well is that some GM's just prefer certain systems. For instance, while I enjoy playing D&D 3.5, I wind up horribly murdering or boring my players if I run most d20 games, just because I'm not as comfortable or adept with those systems. In all the games my group of eight(ish) has gone through, only a few of us will ditto each others' games; we started with Shadowrun and three of us have run that, two of us have run Dark Heresy, and two of us have run Pathfinder.
That doesn't mean that you need to switch systems to accommodate a new GM, especially if the new GM wants to run 3.5, but you might be seeing a case where the GM isn't really aligned with the design philosophy of the game, and that can be a hard thing to work through.