So excited! I just happened to get a chance to look at Steins;Gate stuff again -after I've been too busy for 3+ months-, and what do I find? The Japanese guide book for Steins;Gate 0 was released today (March 31 JST)!!!
For anyone else excited about it, the book is available for international import in printed form from the usual stores like YesAsia and Amazon, but you can also get it legally as an ebook from EbookJapan http://www.ebookjapan.jp/ebj/356790/volume1/
Now, I've got to finish saving up to get a copy... ^^; So hard to wait! XD