Hi Celtic Green
Do you know Celticsblog? That is a very active site for Celtics fans and it is linked to the SB Nation network of blogs (there is one for every NBA team).
Draft Express as well if you are interested in really detailed analysis of a prospective player's strengths and weaknesses.
Inside Hoops does the same thing as Hoops Hype with regard to rumours and collecting a quick excerpt from all the major basketball news articles on a daily basis. Hoops Hype also keeps an extremely useful section showing each team's rosters and salary commitments.
Bill Simmons aka The Boston Sports Guy has his entertaining columns on page 2 of ESPN.com
Wojnarowski's column on Yahoo NBA breaks a lot of big stories.
Look up Larry Coon for anything you ever wanted to know about the Collective Bargaining Agreement (and probably the new one when it is worked out).
82 games.com is a stats nerd's paradise with all kinds of metrics for basketball.
NBA Playbook is a really interesting site that uses video footage of NBA games, etc to demonstrate how different plays work.