If you are wondering to get rid of some apps on your Mac OS X Lion which are purchased from Mac App Store, then the guide below will help out to do that.
How to Delete Apps in OS X Lion
Get logged in on your Mac through administrator account and click on “Launchpad” from dock
Click and hold an icon until all icons start jiggling and then click on “x” button at the upper left on the apps icon to which you want to delete
Then click on “Delete” button on the confirmation dialog box and that’s it.