I am playing this game currently too andI am about 54 hours into it. I actually know where this heart pillar is.

At Flipside from the world gates (where the Return Pipe spits you out at) take the down elevator from here. Flip
and head through the gate in front of Merlon's house and down the hidden path at right. Follow it, then go right and down the pipe. Head left until you find a pipe blocked by...blocks. Bomb them (with Boomer, of course), then take it down.
Head right to a wall, then flip and use Slim to head through the wall (skinny). Place the Pure Heart in the pillar you find.

Hope this helps !!

I went to all the rental places in my city (5 different locations) and none of them had NMH !! I want to try it before I buy it. Also, alot of the rental places in my town do not have a wide selection either. They usually only have 20-25 games for Wii to rent. Anyone else in the same boat ?

I am selling my gamecube !! I have held on to it for long enough after I bought my Wii. I only had it for 6 months before I found a Wii and it is in excellent condition (still had original box and plastic for everything). I also want to put Super Mario Sunshine, Resident Evil 4, Finding Nemo, and 1 or 2 other games with it> I ahve the platinum edition cube with a platinum controller and 2 other controllers (1 third party). How much could I get out of this on ebay or something like it ? Is anyone who reads this interested in buying it ? 8)