How do I remove apps from the LaunchPad?

I just upgraded to OS X Lion last night and one of the first features I wanted to try out was the LaunchPad.
At first I thought I wouldn't like it but I actually like it more than I expected but the only problem for me is it's very cluttered.

For one thing, I have quite a number of apps that are showing up twice. What is causing apps to show up twice and is there a way I can safely remove one without moving the actual app from my computer so that I can still use the app and have it just showing up once?

Next, there are a few apps I'd rather remove from LaunchPad? Some of these are OS X apps such as iChat, Facetime, etc. and others are some apps I've installed. I have seen some instructions on Google about removing apps from LaunchPad but it appears that only works if the app was installed from the Mac App Store.

Thank you for your help.

i have the same problem with launchpad,and it seems that you cannot remove any apps that were installed,i also get a message telling me that i have older versions of mail and safari,the lion tutor app is quite good and gives general insight into the system.