Tutorials or Advice for learning posing

I have recently made a feeble attempt at posing a couple for an engagement shoot (luckily they are friends) and fouled up the posing big time. I was wondering if there were any good tutorials, books, DVD's, etc. that you would reccommend for learning this subject. I also have to work on composition but there is a plethera (if that is spelled right) of info on the web for that. Posing is a lot harder to find. The pictures I took are at the link below. Thanks for any help with this.

http://www.photography​-on-the.net/forum/showthre​ad.php?t=188932

I'm looking for books on this same subject. If I come across any, I'll be sure to post. They're definitely hard to find...

Try browsing magazines of all kinds that have good people photography. No need to limit oneself to wedding mags. Browse everything, glean the best. I do this every once in a while to gain inspiration.