http://www.gofuckyourself.com/showthread.php?t=697720
Thats my thread , but doesnt show how to block no referrer hits..
heres a tool to create a proper htaccess and block no referrer hits to images ( advanced hotlinking )
http://www.htmlbasix.com/disablehotlinking.shtml
my method though is much better than htaccess because all the pictures will still show up. But you can alter the pictures in any way or even randomly