You can redrill some holes in your 9 hole sprocket to accommodate the 32 spoke wheel & from what i've heard from a friend it's NOT as much of a hassle as u might think.
If the hole in the centre of the sprocket is too small you'll need to widen it & widen it accurately cos it needs to be consistant all the way around...possibly take it to a machine shop.
Really your better-off just getting a GOOD 36 spoke wheel & not eff around,but the decision's yours.
See the sprocket on the blue Trek down the bottom:
http://www.zbox.com.au/tips.htm