It was installed when you ran NetBookInstaller, it is part of the mini 9 extensions, I believe.
As far as setting it up, go to System Preferences-Other and click Trackpad to make adjustments.
I've got 2 finger scroll, but this trackpad will never be the same as a macbook, it is just not possible with the hardware being used.
Mini 9 | OS X 10.6.7 | NBI 20100616212351| BIOS 05 | 32 GB Runcore | 2 GIGS RAM
10V | OS X 10.6.7 | NBI 20100616212351 |BIOS 06|160 GB|1 GIG RAM| 6 Cell Dell Battery
Back up Mini 9| OS X 10.6.7| NBI 20100616212351| BIOS 05 | 32 GB SuperTalent | 2 GIGS RAM