The Google desktop search is a new program to search the files on your computer. So far it has worked well for me, it is much better than the search that is built into windows.
On first running it ‘indexes’ all of your files so it can search through them, it only does this when your computer is idle so if you use your computer a lot (or even if you dont) you need to leave your computer for a few hours (I know its hard for some of us, me included, but it just has to be done!), or you could just leave your PC on overnight and it will be done.
I highly recomend this to anyone!