Warm welcome to you @CoconutLaCroix. Super awesome to have you here. It is really a unique collection goal and would love to see your collection and know more on what got you interested in these guides / book and which ones are your favourites.
We also have another collector (@droripory) here who also collects different physical Pokemon media which also includes guides and books as shown in the post here. Maybe you can also find something interesting there. I hope you have a great time with the lovely people here. Looking forward to knowing you a lot more.
Cheers!