There's a great Oral History of Kevin Garnett on bleacher report by Howard Beck. Lots of great stories in there as you might expect.
One that popped out to me was this quote from Ainge about the trade that brought KG to Boston. It turns out it might just have easily gone the other way.
Danny Ainge, Celtics GM: Because Kevin and I were such close friends, we had numerous conversations over the years [about Garnett]. We realized that Paul [Pierce] and KG would be a great combination. We thought that they really complemented each other well.