Does (human) Dean ever buy a kindle or nook for (little) Sam so he can finally read books for fun again or does Sam just use the computer?
Dean hasn’t thought of it, and Sam doesn’t know they exist yet.
Kindles didn’t really become ‘mainstream’ until 2007, and it was a few years after that where they really became popular. Brothers Apart, like Supernatural, starts in 2005, so Dean still has a flip phone during the first few years, and they’re operating on a bulky laptop that he’s had for quite some time.
Sam does take the time to look up books on the computer when he can, and he’s gotten half decent at not getting stuck in books if they start to flip closed on him (Dean’s had to rescue him more than once during research).
It’s just around 2007 as Brothers Apart enters season 3, which is where we left off during the season finale.