Just a corretion for you, the above post was written by 'The One', not by me.
To create a Custom Installer we use either Autoplay Media Studio or CDMenuPro.
Search for them using Google, you can get a trial version to practise with but these trial versions can sometimes stop working after approximately 1 month!
So it is better to actually purchase one of them.
CDMenuPro is probably the easiest to use, but Autoplay Media Studio will give you more options in your installer. It just depends on exactly what you want to do.