As far as sites go these are my regulars. I'm assuming most people know these.
Grantland.com - Not as big of a Simmons fan as I used to be, but plenty of great NBA writing. Especially Zach Lowe. If there is any way someone here doesn't read his stuff, you need to start.
RealGM.com - Great news resource. Jonathan Tjarks is a consistent writer here. Has a very good matter-of-fact perspective.
SBNation.com/nba - Has blogs devoted to every team. Loads of articles from global league perspectives and also more team specific stuff. Just tons of stuff here.
Draftexpress.com - the best nba prospect/draft site.
Basketball-reference.com - great for stats on past seasons.
nba.com/stats - much improved for stats.
Twitter has a bunch of people as well, some of my favorites to follow are
@world_wide_wob sports bettor, knows his stuff but mostly just posts jokey stuff. Obsessed with JR Smith and Javale McGee.
@haralabob probably the most famous NBA bettor. Knows his stuff. Provides consistent insight on specific teams throughout the season.
@wojyahoonba THE news guy.
Then a slew of writers
@teamziller tom ziller of sbnation
@espnsteinline
@daldridgetnt
@draftexpress
@Jonathantjarks
@billsimmons
@kirkgoldsberry the chart guy from grantland
@zachlowe_nba
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