Man, I totally get the hunt for 'FF7 Rebirth' novel content! From what I’ve dug up, Square Enix hasn’t released a standalone novel adaptation of 'Rebirth' yet—it’s more tied to the game’s expanded lore. But if you’re craving deep dives into the world, the 'Final Fantasy VII: On the Way to a Smile' novellas explore post-'Advent Children' events, and they’re floating around on sites like Square Enix’s official store or fan-translated hubs.
For 'Rebirth'-specific stuff, your best bet might be the game’s Ultimania books (when they drop), which usually include prose sections. I’ve snagged older Ultimanias from CDJapan or eBay, though they’re pricey. Meanwhile, the 'FF7 Remake: Trace of Two Pasts' novel covers Tifa and Aerith’s backstories—worth checking if you want more Midgar vibes. Honestly, I’d kill for a proper 'Rebirth' novel too!