This is a step by step tutorial on how to make your own glitter layer style and brushes in Photoshop like in the preview picture.  It is a detailed tutorial with lots of pictures showing you how to make the brushes, set the properties of the brush, and also how to make the layer style that goes with it.   It is in both word and pdf format.   You need Photoshop in order to do this tutorial. 

The tutorial was done in PS CS2, and all screenshots are of CS2, but CS3 is very similar and you will have no problem doing it in that version as well.  I do not know what CS4's interface looks like, so I don't know if it will be any more difficult to do in that version of PS. 

What you make from this tutorial is yours to do with what you want.  I'm just giving you the "how to" part of it, your designs are your own.