The 3DS scene is like an onion: every time you peel back a layer, there’s another one.
The public scene consists of Freeshop and the Titlekeys site it relies on - which enables users to download any game that had its keys dumped, right from their 3DS. The next layer is the forums scene, where Distributors post games in archive format. The scene below that is the Dumpers: those who get their hands on games early and send them to Distributors. The Dumpers primarily communicate via email.
End users download from Repackers (such as Fitgirl, known for her MD5-perfect high-compression repacks), who in turn get their releases from Scene groups… via Usenet. Scene groups are very elite and close-knit. A few of them even eschew tag names, preferring to war against Denuvo in a cloak of silence.