having just been a beginner and now being able to stay upwind etc, board recovery is the easiest thing a beginner can learn. after a stack it's always gonna be 5-15m upwiond of you. get ur kite under control look straight back to spot it then a couple of 15 second drags and you're back to it!
so simple and a good skill to learn anyway.
as for losing it, i remember reading a post by ian young (good advice) to just drag forward and back for about 20-30secs each side and eventually you'll find ur board.
much better than copping the board in the back of the head, i know from experience (not that this occured because of a leash mind you) when a wave dumped the board on to my head. ended up with 7 stitches

and a dent in my board from my head!