Final Fantasy VIII: Remastered was unveiled at E3 and launches next week on September 3 as announced last week at Gamescom, but it'll be a digital-only release. Even though some fans were dreaming of a boxed edition as an item for collectors (there was even some speculation in that regard), Square Enix has made clear it won't be the case.
The game will then follow the same digital path Final Fantasy IX took before it, as noted by the publisher on its official Japanese product page. As such, you'll only be able to purchase FFVIII: Remastered on Nintendo's eShop, PS Store, Xbox Live Store, or Steam.
The same product info specifies the 20-year old classic sold more than 9.6 million copies since its release in 1999, which makes it one of the top-selling FF-games ever.