Edit request from 210.184.231.1, 2 July 2011 

NBA Finals record:
Highest free throw percentage (min. 100 attempts)
92.6% by Bill Sharman (126 made in 136 attempts)

This has been broken by Dirk Nowitzki.
He has made 94/101 free throws (93.1%).

I don't have any source but if you look at his game log below in 2006 and 2011, you can add them up.
http://espn.go.com/nba/player/gamelog/_/id/609/dirk-nowitzki
http://espn.go.com/nba/player/gamelog/_/id/609/year/2006/dirk-nowitzki

210.184.231.1  
 Not done for now: Unless there is a reliable source to me it would be WP:OR