First you will have to download the images you would like to use as brushes (i.e., click on the "ps5.5 image" or "image packs" link to do this).

Now what you have to do is...

These are webbuilder's instructions on how to define a new brush photoshop5.5 or earlier.

In Phtoshop 6 to define a brush go to the "edit" menu and choose "define brush". Make sure brush is no bigger than 1024x1024.

BUT - before you do this here's things to do (in order to save the defined brush for future use).

From the brush menu choose "replace brushes" and then choose a brush set with not too many brushes to load.

After that, right click on each of the brushes and delete them (it won't delete them from the computer so don't worry, you can always reload them) - you won't be able to delete the last one but that's OK.

Now, define your brush as I explained above - then go to the brush menu and delete the brush you couldn't delete before - this will leave only the brush you created.

Now go to the brush menu and choose "save brushes" and give it some name so you can load it again whenever you want. If you want your standard brushes back, from the brush menu choose "reset brush".

And that's it. If you still need help - ask away.