I'm not knocking that tutorial, it looks well worth the money, however, one PhilC's site are severa free tutorials on rigging for poser that are free. They don;t go into weight mapping but you might want to start with the learning poser falloff rigging then jump to the RDNA tutorial once you feel a but more comfortable. I learned originally to do Poser clothing from Phil's DVD MANY years ago and found his teaching style to be very easy to follow.

Here's his site

http://www.philc.net/index.php