I think there are some books available, although I've never read any I would appreciate and read one if someone gave me it. Other than that all of my info is from the clinic and is tailored to our treatment.
Tbh the only thing that I want to read about are things that might improve my chances of success. I don't care much about anything else! So diet tips, studies about success rates, relaxation techniques, benefits of particular holistic therapies, that sort of thing?
Other than that I suppose some people might want to read about the history, science or ethics of ivf. If your sister has a science background she might find that interesting. Although on an abstract level I'm interested in those things, when actually going through it, that goes out the window. I just want it to work.
If you want to help once treatment starts, I think practical things are what I personally would like. Occasional visits where you bring over the dinner ready-made to be heated up, lifts to the hospital, coming round and rather than being waited on, help change the bed, fill the dishwasher and then leave me in peace, texts to ask how I'm (honestly) feeling, that sort of thing? It all depends on her personality and how she's feeling once the treatment starts but lots of people feel really tired and a bit shitty, so gently helping make her life a bit easier might be good? That's what I'd want from my sister, if she wasn't heavily pregnant... 
Hope that helps
you sound like a nice sister