I forget to mention I also like her song "My Lover". It's the recut single from Go Younha, haha.
Anyways, I found the Go Younha Photobook! And yes, it is a First Press only thing. And the photobook is titled "A Day With Younha".
I found it on Cherry Blossom Garden's J-Pop Scans Site:
http://www.gallery.cherryblossom-garden.com/v/younha/
That's the link to the main page of Younha's scans. I'm sure you will be able to find the Photobook from there.
And there are also scans of her albums and singles as well.
And of course, there are lots of other scans from other J-music artists, just browse through their gallery.
